46 Here again is the oath that God swore in his wrath, an oath he swore by himself, that they would not enter the land. “As the Lord lives,” or “by the life of the Lord,” are ways to render it.
47 The word נְאֻם (né’um) is an “oracle.” It is followed by the subjective genitive: “the oracle of the Lord” is equal to saying “the Lord says.”
48 Heb “in my ears.” They had expressed the longing to have died in the wilderness, and not in war. God will now give them that. They would not say to God “your will be done,” so he says to them, “your will be done” (to borrow from C. S. Lewis).

In other versions

Say to them, ‘As I live, declares the Lord, what you have said in my hearing I will do to you:

So tell them, ‘As surely as I live, declares the Lord, I will do to you the very thing I heard you say:

Tell them: As I live—this is the Lord’s declaration—I will do to you exactly as I heard you say.

Now tell them this: ‘As surely as I live, declares the Lord, I will do to you the very things I heard you say.

Say to them, ‘Surely as I live,’ declares Yahweh, ‘just as you spoke in my hearing, so I will do to you;

Say unto them, As truly as I live, saith the Lord, as ye have spoken in mine ears, so will I do to you:

Public Domain