Exodus 20:17

Thou shalt not covet thy neighbor's house, thou shalt not covet thy neighbor's wife, nor his manservant, nor his maidservant, nor his ox, nor his ass, nor anything that is thy neighbor's. Here the thoughts of the entire second table are once more summarized with reference to the source of sin; for it is out of the heart that the evil thoughts proceed which are afterward realized in various actual sins, Matthew 15:19. So the admirable and fitting order of the commandments, as Luther cans it, is brought to an end and the circle of injunctions completed; for it is only by the sanctification of the heart according to the Tenth Commandment that the true worship of God according to the First Commandment can be secured. It should be noted here that both the division of the Decalogue as such and the distinction between the Ninth and the Tenth Commandment are matters of no material consequence.