And I will make you swear by the LORD: make you swear is the literal Hebrew form. More natural in English is “and swear” or “and make a vow.” For discussion of swear see 14.22; 21.23.

The God of heaven and of the earth: this expression stands in apposition to the LORD; that is, it adds a title or description to the name: “The LORD who is the God of heaven and the earth.” God of heaven and … may be rendered as “God who created heaven and…,” “God who rules heaven and…,” “God who is over heaven and….”

Stated simply, what Abraham is asking his servant to swear or promise to do in verses 3b-4 has two elements:
(1) a positive condition requiring the servant to choose a woman from among Abraham’s relatives in Mesopotamia, and
(2) a negative condition warning him not to choose a Canaanite woman.

In the Hebrew text and most English versions, the order of these elements is 2, 1; that is, the negative condition is stated first and the positive command last. However, in many languages this is not a natural order for giving instructions, and the text will need to be restructured to the order 1, 2, or at least to give the essential part of the command first (“get a wife for my son Isaac”). See the end of verse 4 for one model of such restructuring.

That you will not take a wife for my son: take a wife means more than to pick out or choose a woman. It refers to making the marriage arrangements. The expression used should reflect the expression used for arranging for or contracting for a wife between families. This is often something like “cause my son to marry” or “marry my son to….” Biblia Dios Habla Hoy says “that you will not allow my son Isaac to marry….” In some languages the term for wife is “woman,” while in others it is necessary in this context to speak of “bride” or “future wife.”

From the daughters of the Canaanites: the reference is to the Canaanite females, that is, “from the Canaanite women.” Good News Translation generalizes by saying “from the people here in Canaan.”

Among whom I dwell: this is adequately expressed by Good News Translation “here.” In reference to intermarriage with Canaanite women, see Josh 23.12.

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 .