Numbers 23:10 - Matthew Poole's English Annotations on the Holy Bible

The dust of Jacob, i.e. the numberless people of Jacob or Israel, who, according to God's promise; Genesis 13:16, Genesis 28:14, are now become as the dust of the earth. Of the fourth part of Israel, i.e. of one of the camps of Israel; for they were divided into four camps, Num 2, which Balaam from this height could easily discover; much less can any man number all their host. Of the righteous, i.e. of his righteous and holy people, the Israelites, called Jehesurun, Deuteronomy 32:15, which word signifies upright or righteous. The sense is, they are not only happy above other nations in this life, as I have said, and therefore in vain should I curse them, but they have this peculiar privilege, that they are happy after death; their happiness begins where the happiness of other people ends; and therefore I heartily wish that my soul may have its portion with theirs when I die. But it was a vain wish; for as he would not live as God's people did, so he died by the sword, as others of God's enemies did, Numbers 31:8 Joshua 13:22. My last end, i.e. my death, as the word is used. Or, my posterity, as this Hebrew word signifies, Psalms 119:13 Daniel 11:4 Amos 4:2. And as the covenant and blessing of God given to Abraham did reach to his posterity, so this might not be unknown to Balaam, which might give him occasion for this wish. Or, my reward, as the word is taken, Proverbs 23:18, Proverbs 24:20. But the first sense seems the most true, because it agrees best with the usage of Scripture to repeat the same thing in other words, and this includes the third sense, to wit, the reward, which is here supposed to follow death; and for posterity, it doth not appear that he had any, or, if he had, that he was so very solicitous for them; or that he knew the tenor of God's covenant with Abraham and his posterity. Nay, he rather seems to have had some hope of ruining Abraham's posterity, which he attempted both here and afterwards.