13 Heb “will your name be called.”
14 Your name will be Abraham. The renaming of Abram was a sign of confirmation to the patriarch. Every time the name was used it would be a reminder of God’s promise. “Abram” means “exalted father,” probably referring to Abram’s father Terah. The name looks to the past; Abram came from noble lineage. The name “Abraham” is a dialectical variant of the name Abram. But its significance is in the wordplay with אַב־הֲמוֹן (’av-hamon, “the father of a multitude,” which sounds like אַבְרָהָם, ’avraham, “Abraham”). The new name would be a reminder of God’s intention to make Abraham the father of a multitude. For a general discussion of renaming, see O. Eissfeldt, “Renaming in the Old Testament,” Words and Meanings, 70–83.
15 The perfect verbal form is used here in a rhetorical manner to emphasize God’s intention.

In other versions

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.

No longer will you be called Abram; your name will be Abraham, for I have made you a father of many nations.

Your name will no longer be Abram; your name will be Abraham, for I will make you the father of many nations.

What’s more, I am changing your name. It will no longer be Abram. Instead, you will be called Abraham, for you will be the father of many nations.

Your name shall no longer be called Abram, but your name shall be Abraham, for I will make you the father of a multitude of nations.

Neither shall thy name any more be called Abram, but thy name shall be Abraham; for a father of many nations have I made thee.

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