By myself I have sworn: the LORD has called upon his own name in an oath. For sworn see discussion of 21.23. If it is unnatural in the language of translation for God to swear on himself, translators may use a more general expression such as “I have promised,” “I have declared,” “I have solemnly said.” Says the LORD is a solemn affirmation that what is being said comes directly from God. It is used frequently in the prophets but occurs far less frequently elsewhere. Good News Translation “—the LORD is speaking—” inserts this expression as an interruption in the angel’s message. Revised English Bible begins the angel’s quote with “This is the word of the LORD:….” Bible en français courant has “This is what the Lord declares:….” We may also say, for example, “These are the LORD’s own words: ‘I have sworn…’ ” or “Hear what the LORD says to you: ‘I have made a promise….’ ”

Because you have done this: this refers to obeying God and preparing to sacrifice Isaac.

And have not withheld your son, your only son: for wording see verse 12. If the English construction is not suitable for translation, the reason clause because you … may be expressed as a statement, and then verse 17 treated as a consequence of this: “You obeyed me and have not held back your son…; therefore….” Another way of restructuring this passage is “This son is the only one you have, and you have not held on to him. Because you have done this, I promise you that….”

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 .