So he went in to his father: since this is an action that follows the event in verse 17, something equivalent to “Then” or “After that” may be more suitable. In some languages the transition to the place where Isaac is may need to be expressed more fully; for example, “Carrying the food in his hands, Jacob went to the room where his father was.”

My father: the form of address should be appropriate for this situation in the language and culture of the readers. It should be recalled that Jacob does not want to reveal who he really is.

And he said: he is Isaac, and this may need to be stated as “Isaac said.”

Here I am: Isaac’s reply is nearly the same as Abraham gave to God in 22.1. Isaac is not telling his son where to look for him in the room but is responding to Jacob’s words. In translation Isaac’s response should match the situation. In some cases this may be “I hear you,” “You’ve come,” “You say so.” Note Good News Translation “Yes.”

Isaac must be certain that he is dealing with his older son and so inquires who are you, my son? Isaac’s question does not mean that the voice he has heard is from a total stranger. He wishes only to distinguish between Esau and Jacob; that is, “Which of my sons are you?” See Good News Translation.

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .