Abram Becomes Abraham

Genesis 17:1–18:15

In this story, covenant promise becomes more explicit in identity markers. Abram is renamed Abraham, and Sarai is renamed Sarah. The new names align with expanded promise and vocation. God also appoints circumcision as a covenant sign for Abraham's household. The following scene at Mamre joins hospitality and revelation: three visitors announce that Sarah will bear a son. Her laughter marks both honest impossibility and the beginning of transformed expectation.

The Name Change and the Covenant Sign

God appears to Abram and says: "I am God Almighty; walk before me, and be blameless, that I may make my covenant between me and you, and may multiply you greatly."

Then God changes his name:

"No longer shall your name be called Abram, but your name shall be Abraham, for I have made you the father of a multitude of nations." — Genesis 17:5 (ESV)

The name change is covenant theology in narrative form. Calvin has emphasized that identity is received from God's word, not self-constructed. Abram becomes Abraham—"father of a multitude"—because God declares it. The name embodies the promise.

God also institutes circumcision as a covenant sign:

"Every male among you shall be circumcised. You shall be circumcised in the flesh of your foreskins, and it shall be a sign of the covenant between me and you." — Genesis 17:10–11 (ESV)

Circumcision is a physical sign in the flesh of covenant households. The command extends beyond Abraham himself to sons and servants, emphasizing that covenant identity has communal dimensions. It is not a private matter; it involves the whole household.

Sarah and Isaac

Sarai is renamed Sarah. God specifies that she will bear the promised son. Abraham laughs at the prospect. He is old—nearly one hundred years old. Sarah is ninety. How can they have a child?

Abraham asks: "Oh that Ishmael might live before you!" He is asking whether Ishmael, the son born to Hagar, might be the covenant heir.

God responds: "No, but Sarah your wife shall bear you a son, and you shall call his name Isaac." God blesses Ishmael with fruitfulness—he will become a great people—but clearly identifies Isaac as the covenant heir.

Abraham obeys. That same day, he circumcises himself and all the men of his household.

The Visitors at Mamre

At the oaks of Mamre, Abraham receives three visitors. He runs to meet them, bows, and offers hospitality with urgency. He brings water for their feet, prepares a meal, and stands by them while they eat.

During the meal, the promise is repeated: "I will surely return to you about this time next year, and Sarah your wife shall have a son."

Sarah hears this from inside the tent. She laughs internally. The announcement collides with age and barrenness. She thinks: "After I am worn out, and my lord is old, shall I have pleasure?"

Then one of the visitors asks: "Why did Sarah laugh and say, 'Shall I indeed bear a child, now that I am old?' Is anything too hard for the Lord?"

This question becomes thematic in Scripture: "Is anything too hard for the Lord?" Jewish interpreters have often highlighted Abraham's hospitality in Genesis 18 as exemplary righteousness, showing that covenant faith is lived in ordinary practices of welcome. But the scene also presents revelation: God Himself comes to Abraham in the form of visitors, and the promise is confirmed.

Christian interpreters commonly read Sarah's laughter as mixed: disbelief and wonder intertwined. The text does not erase her weakness but redirects it toward trust in divine power. She laughed in disbelief, but the promise will be fulfilled.

What to Notice

Names embody identity and promise. Abram becomes Abraham—"father of a multitude." The name change is not merely symbolic; it declares who he will become.
Covenant signs are embodied and communal. Circumcision is a physical mark in the flesh, and it involves the whole household. Covenant faith is not abstract; it is lived in the body and in community.
God distinguishes the covenant heir. Isaac is identified as the covenant heir, while Ishmael is blessed with fruitfulness. Both are under God's care, but the covenant line narrows through Isaac.
Hospitality and revelation are joined. Abraham's welcome of the visitors becomes the occasion for God's revelation and the confirmation of the promise.
Laughter can express both doubt and wonder. Sarah's laughter is honest about the impossibility of the situation, yet it also marks the beginning of transformed expectation.