Genesis 25:26

And after that came his brother out, and his hand took hold on Esau’s heel; and his name was called Jacob: and Isaac was threescore years old when she bare them.

Cross-reference

Genesis 27:36 references Jacob's name 'supplanter,' linking to his heel-grasp and theft of blessing.

Hosea 12:3 directly cites Jacob's heel-grasp in the womb, interpreting it as early strength.