GENESIS: God Uses Every Situation in Our Lives to "work together for good to those who love God, to those who are the called according to His purpose"; "Then Abimelech took sheep, oxen, and male and female servants, and gave them to Abraham; and he restored Sarah his wife to him."

And Abraham journeyed from there to the South, and dwelt between Kadesh and Shur, and stayed in Gerar. Now Abraham said of Sarah his wife, “She is my sister.” And Abimelech king of Gerar sent and took Sarah. (Genesis 20:1-2)

It is inconceivable that Abraham would do this same thing again, go into another country and have his wife lie that she is his sister so that the men would not do him any harm.  He did this same thing when he and Sarah went to Egypt, and Abram went down to Egypt to dwell there, for the famine was severe in the land. And it came to pass, when he was close to entering Egypt, that he said to Sarai his wife, “Indeed I know that you are a woman of beautiful countenance. Therefore it will happen, when the Egyptians see you, that they will say, ‘This is his wife’; and they will kill me, but they will let you live. Please say you are my sister, that it may be well with me for your sake, and that I may live because of you.” (Genesis 12:10-13)

But God came to Abimelech in a dream by night, and said to him, “Indeed you are a dead man because of the woman whom you have taken, for she is a man’s wife.” But Abimelech had not come near her; and he said, “Lord, will You slay a righteous nation also? Did he not say to me, ‘She is my sister’? And she, even she herself said, ‘He is my brother.’ In the integrity of my heart and innocence of my hands I have done this.” (Genesis 20:3-5)

And God said to him in a dream, “Yes, I know that you did this in the integrity of your heart. For I also withheld you from sinning against Me; therefore I did not let you touch her. Now therefore, restore the man’s wife; for he is a prophet, and he will pray for you and you shall live. But if you do not restore her, know that you shall surely die, you and all who are yours.” (Genesis 20:6-7) 

We can't help but see how fair God is, "Against You [God], You only, have I sinned, and done this evil in Your sight— that You may be found just when You speak, and blameless when You judge." (Psalm 51:4) When we sin, God will rightly judge us, but He warns us. He did the same with Pharaoh when Abraham and Sarah were in Egypt. But the Lord plagued Pharaoh and his house with great plagues because of Sarai, Abram’s wife. And Pharaoh called Abram and said, “What is this you have done to me? Why did you not tell me that she was your wife? Why did you say, ‘She is my sister’? I might have taken her as my wife. Now therefore, here is your wife; take her and go your way.” So Pharaoh commanded his men concerning him; and they sent him away, with his wife and all that he had. (Genesis 12:17-20)

So Abimelech rose early in the morning, called all his servants, and told all these things in their hearing; and the men were very much afraid. And Abimelech called Abraham and said to him, “What have you done to us? How have I offended you, that you have brought on me and on my kingdom a great sin? You have done deeds to me that ought not to be done.” Then Abimelech said to Abraham, “What did you have in view, that you have done this thing?” (Genesis 20:8-10)

Exactly, why would Abraham do such a thing, especially after all that God had done for him from the time he left Egypt up to this time?  He finally explains. And Abraham said, “Because I thought, surely the fear of God is not in this place; and they will kill me on account of my wife. But indeed she is truly my sister. She is the daughter of my father, but not the daughter of my mother; and she became my wife. And it came to pass, when God caused me to wander from my father’s house, that I said to her, ‘This is your kindness that you should do for me: in every place, wherever we go, say of me, “He is my brother.”’” (Genesis 20:11-13)

So he tried to justify himself because it wasn't completely untrue that Sarah was his sister.  But based on how God responded in both cases, he was not justified, but God saw it as lying.  Sarah was his wife, and that was the only relationship that mattered. Brethren, if a man is overtaken in any trespass, you who are spiritual restore such a one in a spirit of gentleness, considering yourself lest you also be tempted. (Galatians 6:1) God restored Abimelech, and now Abimelech would restore Abraham.

Then Abimelech took sheep, oxen, and male and female servants, and gave them to Abraham; and he restored Sarah his wife to him. And Abimelech said, “See, my land is before you; dwell where it pleases you.” Then to Sarah he said, “Behold, I have given your brother a thousand pieces of silver; indeed this vindicates you before all who are with you and before everybody.” Thus she was rebuked. (Genesis 20:14-16)

God had Pharaoh allow Abraham to leave with all he came there with; but now, Abimelech would give him more than what he had when he came. Brethren, if anyone among you wanders from the truth, and someone turns him back, let him know that he who turns a sinner from the error of his way will save a soul from death and cover a multitude of sins. (James 5:18-19) So Abraham prayed to God; and God healed Abimelech, his wife, and his female servants. Then they bore children; for the Lord had closed up all the wombs of the house of Abimelech because of Sarah, Abraham’s wife. (Genesis 20:17-18)

Fast-forward in time, And it came to pass at that time that Abimelech and Phichol, the commander of his army, spoke to Abraham, saying, “God is with you in all that you do. Now therefore, swear to me by God that you will not deal falsely with me, with my offspring, or with my posterity; but that according to the kindness that I have done to you, you will do to me and to the land in which you have dwelt.” And Abraham said, “I will swear.” (Genesis 21:22-24)

Then Abraham rebuked Abimelech because of a well of water which Abimelech’s servants had seized. And Abimelech said, “I do not know who has done this thing; you did not tell me, nor had I heard of it until today.” So Abraham took sheep and oxen and gave them to Abimelech, and the two of them made a covenant. And Abraham set seven ewe lambs of the flock by themselves. (Genesis 21:25-28)

Then Abimelech asked Abraham, “What is the meaning of these seven ewe lambs which you have set by themselves?” And he said, “You will take these seven ewe lambs from my hand, that they may be my witness that I have dug this well.” Therefore he called that place Beersheba [meaning well of an oath], because the two of them swore an oath there. (Genesis 21:29-31)

Thus they made a covenant at Beersheba. So Abimelech rose with Phichol, the commander of his army, and they returned to the land of the Philistines. Then Abraham planted a tamarisk tree in Beersheba, and there called on the name of the Lord, the Everlasting God. And Abraham stayed in the land of the Philistines many days. (Genesis 21:32-34) 

God promised Abraham from the beginning of his journey that he would give him the land of the Canaanites, And he believed in the Lord, and He accounted it to him for righteousness. Then He said to him, “I am the Lord, who brought you out of Ur of the Chaldeans, to give you this land to inherit it.” (Genesis 15:6-7) Through many Divinely orchestrated events, God was indeed increasing Abraham's territory. God keeps his promises! If we are faithless, He remains faithful; He cannot deny Himself. (II Timothy 2:13) AMEN!