The LORD shall bless thee out of Zion: and thou shalt see the good of Jerusalem all the days of thy life.
The Lord shall bless thee out of Zion - His seat, whence, out of His 'sanctuary' there, He distributes abroad His benefits (Psalms 20:2).
And thou shalt see the food of Jerusalem all the days of thy life - literally, imperative see; implying the certainly of the promise. So the imperative, Psalms 37:27. Jerusalem is the center of national and spiritual life and light to the whole land. Its prosperity involves that of the nation (Psalms 122:1-3; Psalms 122:6).