The LORD that made heaven and earth bless thee out of Zion. The Lord that made heaven and earth - Who governs and possesses all things; and who can give you every spiritual and earthly blessing.
Bless thee out of Zion - As if they had said, "We will attend to your orders; go in peace, and may God shower down his blessings upon you!" The blessing pronounced by the priests was the following: "The Lord bless thee and keep thee! The Lord make his face shine upon thee, and he gracious unto thee! The Lord lift up his countenance upon thee, and give thee peace!" Numbers 6:24-26.
Commentary on the Bible, by Adam Clarke [1831].