Esodo 20:3

Thou shalt have no other gods before me. Thou shalt have no other gods before me - אלהים אחרים elohim acherim, no strange gods - none that thou art not acquainted with, none who has not given thee such proofs of his power and godhead as I have done in delivering thee from the Egyptians, dividing the Red Sea, bringing water out of the rock, quails into the desert, manna from heaven to feed thee, and the pillar of cloud to direct, enlighten, and shield thee.

By these miracles God had rendered himself familiar to them, they were intimately acquainted with the operation of his hands; and therefore with great propriety he says, Thou shalt have no strange gods before me; על פני al panai, before or in the place of those manifestations which I have made of myself.

This commandment prohibits every species of mental idolatry, and all inordinate attachment to earthly and sensible things. As God is the fountain of happiness, and no intelligent creature can be happy but through him, whoever seeks happiness in the creature is necessarily an idolater; as he puts the creature in the place of the Creator, expecting that from the gratification of his passions, in the use or abuse of earthly things, which is to be found in God alone.

The very first commandment of the whole series is divinely calculated to prevent man's misery and promote his happiness, by taking him off from all false dependence, and leading him to God himself, the fountain of all good.