Genesis 21:1-21.
God Fulfills His Promises

American Journal of Biblical Theology,
Copyright © 2015, Dr. John W. (Jack) Carter     Scripture quotes from KJV

There is no question that life is full of events and decisions that serve to cause us stress and distract us from the peace and joy of the abundant life that God has promised to those who put their faith and trust in Him.  When we are involved in the day-to-day decision making of our lives, do we make choices based upon our own logical conclusions, or do we seek Godís purposes and plans?  We often depend upon our own viewpoints and our own desires, leaving God out of our decision making process, and then find ourselves regretting our lack of wisdom.  When we leave God out of our decisions, we are demonstrating a lack of trust in God who promises that abundant life.  God's promises, and the comfort in the Holy Spirit that they bring, can become a source of strength and direction in decision making.  We can find solutions and stability through studying God's promises and praying about all decisions. 

What are some ways that God has fulfilled promises in your life?  He has promised you:

  • Freedom from anxiety (Philippians 4:6,7; Psalm 91:1; Matthew 11:29)

  • The return of Jesus Christ (John 14:2,3; Matthew 25:31; Titus 2:11-13)

  • No condemnation (Romans 8:1; 1 Thessalonians 5:9; 1 Peter 1:5)

  • Protection from death (1 Thess.  4:13; John 5:24; 1 Corinthians 15:54)

  • Freedom from fear (Isaiah 41:10; Joshua 1:9; John 14:27)

  • the benefits of faith (Hebrews 11:1; Ephesians 2:8-9; 1 John 5:4)

  • Adequate finances (Matthew 6:33; Malachi 3:10; II Corinthians 9:8)

  • Forgiveness (1 John 1:9; Psalm 103:12; Isaiah 1:18)

  • Hope (Psalm 33:18, Colossians 1:27, 1 Peter 1:3)

  • Peace (Philippians 4:7; John 16:33; Romans 5:1)

  • Salvation (John 3:16; Ephesians 2:8,9; Romans 10:9,10)

  • Overcoming The World (1 John 5:4,5; 1 John 4:4; John 16:33)

  • A Trustworthy God (Proverbs 3:5,6; Isaiah 26:3,4; Psalm 31:19,20)

  • Healing (Acts 3:16; James 5:14,15; Matthew 9:22)

  • Assurance of Salvation (Psalm 103:12; Isaiah 44:22; John 10:27-29)

  • You are a child of God (Romans 8:16,17; Matthew 5:9; Luke 20:36)

  • Heaven (1 Corinthians 2:9; Revelation 2:7; Matthew 6:19-21

  • Eternal life (John 3:16; John 4:14; John 3:36

  • Direction in life (Matthew 6:33; James 4:7,8; Hebrews 11:6)

  • Provision of needs (Matthew 6:25,26; 1 Peter 5:6,7; Philippians 4:6,7)

Godís promises are sure, and are given to those who love Him.  However, the realization of those promises is predicated upon obedience.  When we disobey God, we bring upon ourselves all manner of consequences, circumstances and difficulties that may supplant Godís plan for our lives.  We can find an example in scripture of how God worked through the circumstances and decisions in Abrahamís life to bring His promises to fulfillment.

1.  The Fulfillment of a Promise

Genesis 21:1-2.  And the LORD visited Sarah as he had said, and the LORD did unto Sarah as he had spoken.  2For Sarah conceived, and bare Abraham a son in his old age, at the set time of which God had spoken to him.

The promise that God fulfilled was given to Abraham on three occasions, each at important points in his life.

Genesis 18:10-14.  And he said, I will certainly return unto thee according to the time of life; and, lo, Sarah thy wife shall have a son.  And Sarah heard it in the tent door, which was behind him.  11Now Abraham and Sarah were old and well stricken in age; and it ceased to be with Sarah after the manner of women.  12Therefore Sarah laughed within herself, saying, After I am waxed old shall I have pleasure, my lord being old also? 13And the LORD said unto Abraham, Wherefore did Sarah laugh, saying, Shall I of a surety bear a child, which am old? 14Is any thing too hard for the LORD? At the time appointed I will return unto thee, according to the time of life, and Sarah shall have a son.

When God first communicated His promise, Abraham and Sarah were about 75 and 65 years old, long past the age of childbearing, and approaching or past the late life expectancy of their day.  What promise did God make to Sarah?  After an appointed time, Sarah would bear a child of her own.  Such a promise sounded ridiculous, and Sarah is famous for having scorned the promise with her disbelief.  The appointed time that God referred to turned out to be about 25 years.  The scorn of the promise was not one that lasted a few minutes.  It lasted for 25 years while Sarah was aging and remained barren.  God again repeated the promise when they were so aged:

Genesis 17:15-19.  And God said unto Abraham, As for Sarai thy wife, thou shalt not call her name Sarai, but Sarah shall her name be.  16And I will bless her, and give thee a son also of her: yea, I will bless her, and she shall be a mother of nations; kings of people shall be of her.  17Then Abraham fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is an hundred years old? and shall Sarah, that is ninety years old, bear? 18And Abraham said unto God, O that Ishmael might live before thee! 19And God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him.  

God would change Sarai's name, indicating that He had the authority to so.  The name Sarai refers to a princess: the child of a king.  However, the name Sarah also refers to a princess, but one who would be the mother of kings.   She would have a basic change in personality and world-view that would result from the birth.  She would be changed from one who lived in scorn, doubt, sorrow and bitterness to one who lived in joy and hope.  God also promised that she would indeed bear the son of this promise herself, through this son she would be the mother of great nations, and God would establish an eternal covenant with the son and those that follow him.

However, Abraham and Sarah, in their doubts, took the matter into their own hands and chose to help the promise along a little by having a child Sarahís younger handmaiden, Hagar.  She bore a son by Abraham, whom they named Ishmael, assuming that this would be the child of the promise.  The concept that Sarah could yet bear a child was simply not yet believable to them.

Genesis 17:20-21.  And as for Ishmael, I have heard thee: Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation.  21But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year.

The twelve sons of Ishmael are Nebaioth, Kedar, Adbeel, Mibsam, Mishma, Dumah, Massa, Hadad, Tema, Jetur, Naphish and Kedemah (Genesis 25:13-15).  However, God's covenant would be made with Isaac and his sons, not with Ishmael.  Isaacís sons were Esau and Jacob.  We do see some similarities between Abraham's sons and Isaac's sons:  (1) the second son would receive the blessing, and (2) the sons and their descendants would be in conflict with one another from that day on.  Even today, the bulk of Israelís enemies come from the sons of Ishmael.  The world culture dictated that the blessing of inheritance would always go to the first-born son.  God made no such restriction in His promise of blessing, since His promise of blessing is given based upon the attitude of oneís heart, not their physical birth order 

Addressing Abraham and Sarahís doubts, God now put a calendar date on the birth of Isaac: one more year.

God would bless Ishmael with twelve sons who would be the fathers of nations of people as they would populate the region.  God would also bring twelve sons to Isaacís son, Jacob who would also be fathers of nations as they populated the same region.  Throughout all of the time of God's fellowship with mankind, he has been actively working with them.  Note that as he provided a remnant of the faithful in the nations of Israel to maintain his covenant, it was God who also provided the people who would be in conflict with them.  The nations of Ishmael and the nations of Israel have always been engaged in a blood-feud that goes back to the manner of their initial division.  Why would God allow this to be?  By ordaining a purpose for the nations of Ishmael (and of Jacobís brother Esau), God put in motion circumstances that would show the nations if Israel their need for God.  This really drives home the concept that though God created all mankind, He made the everlasting covenant with a remnant of them.

Since God kept his promises with Abraham and Sarah, what can we expect from Him?  We can have confidence in the same faithfulness and exactness in the fulfillment of the promises he makes to us.  How does God make promises to us?  We find His promises through his revealed Word: the scriptures, and through their implementation in our lives through the leadership and guidance of the Holy Spirit.

Genesis 21:3-7.  And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac.  4And Abraham circumcised his son Isaac being eight days old, as God had commanded him.  5And Abraham was an hundred years old, when his son Isaac was born unto him.  6And Sarah said, God hath made me to laugh, so that all that hear will laugh with me.  7And she said, Who would have said unto Abraham, that Sarah should have given children suck? for I have born him a son in his old age. 

The Joyful Name.

Names that were given in the ancient near-east carried a tremendous significance as they served to describe the character of the individual.  Most see the name of Isaac, or Yitschaq, containing the root for the Hebrew word laughter.  Literally, the name means, ďhe laughed.Ē  Derivatives of this word are used for the various words that refer to different forms of laughter and scorn.

There are two schools of thought concerning the name given to Isaac.  The first, and most popular, is that though the root word clearly refers to mockery, Abraham and Sarah saw the name purely from the point of view of joyful laughter.  It is evident in verse 6 that Sarah certainly felt this way.  The second school of thought is more literal, in that the name for mockery would always remind Abraham and Sarah that they mocked God when he pronounced his promises to them.  They will always be reminded of their lack of faith at that time of their lives.

It is reasonable that both are true.  As Abraham receive great joy from the child, they are reminded that Isaac will always represent the faithfulness of God to keep his promises even when our faith is weak.

Genesis 21:8-11.  And the child grew, and was weaned: and Abraham made a great feast the same day that Isaac was weaned.  9And Sarah saw the son of Hagar the Egyptian, which she had born unto Abraham, mocking.  10Wherefore she said unto Abraham, Cast out this bondwoman and her son: for the son of this bondwoman shall not be heir with my son, even with Isaac.  11And the thing was very grievous in Abrahamís sight because of his son.

The Consequence of Disobedience.

What was Abraham's response when Isaac was weaned, that is, no longer a baby and now having passed the period of infancy, is ready to grow as a child?  Abraham is joyful and excited.  He probably can barely contain himself when he thinks of his son and the future that awaits him.  In order to express his joy, he made a great feast.

What was Ishmael's response to the weaning of Isaac?  Ishmael is now nearly 16 years old, at an age that he is considered to be an adult.  Ishmael was mocking Abraham, Isaac, and their celebration of the promise, certainly showing disrespect towards his father and contempt towards his half-brother.  It is clear that his is not the blessing of the first-born and his resentment is no secret. 

Sarah's was the stereotypical Hebrew mother, the yenta who was concerned that her son might have to share in the inheritance with Hagar's son, one who was not her own.  Because of the disrespect he was showing, she was determined that he would get nothing.  Even the lowest of the slaves or workers in Abraham's tribal group still had the benefits of being an accepted part of the group, including food, shelter, protection, etc.  What did Sarah want for Ishmael?  She wanted him removed entirely from the family community so that Isaac could receive all of the inheritance.  God had already made a promise to Sarah and Abraham concerning the inheritance that would be given to Isaac.  It was never necessary that Sarah turn out Ishmael and Hagar.  Again Abraham and Sarah doubted God's promises!

Also, what does this say about Sarah's consideration of Abraham's feelings towards his son?  Abraham loved Ishmael.  Because of Sarahís doubts, Abraham would suffer pain as they again take it upon themselves to bring about Godís promise, using their own methods.  The consequence was huge, as a family that would have been formed from 24 nations was forever divided.  When does pain and conflict generally come to families?   Many difficulties are realized when we act out of motives other than love, or respond to the effects of others who treat us out of similar motives. 

Genesis 21:12-14.  And God said unto Abraham, Let it not be grievous in thy sight because of the lad, and because of thy bondwoman; in all that Sarah hath said unto thee, hearken unto her voice; for in Isaac shall thy seed be called.  13And also of the son of the bondwoman will I make a nation, because he is thy seed.  14And Abraham rose up early in the morning, and took bread, and a bottle of water, and gave it unto Hagar, putting it on her shoulder, and the child, and sent her away: and she departed, and wandered in the wilderness of Beersheba.

God's Compassionate Concern

How did God show his concern for Abraham?  The promise that He made to Abraham was sure.  Godís compassion for Ishmael was the same as that for Isaac, and the only difference in Godís plan for the two sons was the promise to bring the blessing to the nations through Isaac.  So, God assured Abraham that He also had plans for Ishmael that were similar to those for Isaac.  God had a place for Ishmael and would also make of him a great nation.  The decision to cast out Hagar and Ishmael was a difficult one for Abraham, and doing so established a resentment in Ishmael that would characterize the relationships between the nations forever.  Yet, God gives us the ability to deal with tough decisions when we seek Him in them.  God is always ready and willing to help.  A good toolbox verse for this is Matthew 6:33: "Seek ye first the kingdom of God, and His righteousness, and all these things will be added unto you."  God is ready and willing to provide His wisdom and assurance for us in times of decision-making.

Genesis 21:15-21.  And the water was spent in the bottle, and she cast the child under one of the shrubs.  16And she went, and sat her down over against him a good way off, as it were a bowshot: for she said, Let me not see the death of the child.  And she sat over against him, and lift up her voice, and wept.  17And God heard the voice of the lad; and the angel of God called to Hagar out of heaven, and said unto her, What aileth thee, Hagar? fear not; for God hath heard the voice of the lad where he is.  18Arise, lift up the lad, and hold him in thine hand; for I will make him a great nation.  19And God opened her eyes, and she saw a well of water; and she went, and filled the bottle with water, and gave the lad drink.  20And God was with the lad; and he grew, and dwelt in the wilderness, and became an archer.  21And he dwelt in the wilderness of Paran: and his mother took him a wife out of the land of Egypt.

Blessings from God.

Hagar and Ishmael's provisions became depleted.  They became exhausted and dehydrated.  Their situation had become desperate when Ishmael collapsed in the heat.   In an effort to try to protect Ishmael from the sun and to keep him from seeing her despair, Hagar sat him down under a shrub and went far enough away that he would not hear her cry.  God heard Hagar and Ishmael's cries, and He drew her attention to a nearby well of water.  Hagar filled the water skin, and gave it to Ishmael in order that he might drink.  As we might expect, God continued to be with Ishmael.  As God had promised, he became the father of a great nation.  Though this entire experience we can see the conflict that was brought to bear when Abraham and Sarah doubted the promises that God made to them.  Godís plan for them never changed as they continued to act upon their doubts.  He loved them and both of their sons, and had plans to bless all of them. 


  • God communicates His promises to us through His word, through prayer, through circumstances, and through the testimonies of other Christians.

  • Godís promises come from one who is infinitely wiser than we, and one who can accomplish anything He desires. 

  • We are foolish to doubt His promises, and we will always fall into error when we act upon those doubts.

  • We should share with others the joyful fulfillment of God's promises to us.

  • As members of the community of faith, we must show a spirit of love and forgiveness.

  • God always is ready and willing to help us make our decisions, even when they are difficult and painful ones.