Aaron and his sons - shall wait on their priest's office - It was the business of the priests to offer the different sacrifices to God; to consecrate the shew-bread, pour out the libations, burn the incense, sprinkle the blood of the victims, and bless the people. In a word, they were the servants of God alone.

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The Fifth Commandment
Honour thy father and thy mother: that thy days may be long upon the land which the Lord thy God giveth thee.' Exod 20: 12. Having done with the first table, I am next to speak of the duties of the second table. The commandments may be likened to Jacob's ladder: the first table respects God, and is the top of the ladder that reaches to heaven; the second respects superiors and inferiors, and is the foot of the ladder that rests on the earth. By the first table, we walk religiously towards God; by …
Thomas Watson—The Ten Commandments