Albert Barnes Commentary Psalms 128:5

"Jehovah bless thee out of Zion: And see thou the good of Jerusalem all the days of thy life." — Psalms 128:5 (ASV)

The Lord shall bless thee out of Zion - He will not merely bless you in the field and in the house, but will add blessings that seem to come more directly from Zion, or that seem to be more directly connected with religion: He will bless you with religious influences in your own family; He will bless you by permitting you to see the growth of the church and the conversion of souls.

And thou shalt see the good of Jerusalem - The prosperity, the happiness of Jerusalem: that is, the good of the church; the advancement of pure religion. The Hebrew might be rendered, “And look you upon the good of Jerusalem” — in the imperative; and, thus rendered, it would be a command to regard, in these circumstances, the welfare of Jerusalem, or the prosperity of the church. But the language also admits the other construction, and the connection seems to require it. Thus understood, it is a promise that the one referred to would be permitted to enjoy a view of the continual prosperity of religion in the world.

All the days of thy life - To the very close of life. No higher blessing could be promised to a pious man than that he should see religion always prospering; that the last view he would have of the world should be the rapid advances of religion; that he should die in a revival of religion.