De Specialibus Legibus (lib. i‑iv)

In the same way let not him who honours his parents dutifully seek for any further advantage, for if he considers the matter he will find his reward in his own conduct. Not but what, since this commandment is inferior in importance to the first five commandments, which have a more divine character, inasmuch as this is concerned with mortal subjects, God has given an inducement to obey this one, saying, "Honour thy father and thy mother, that it may be well with thee, and that thy days may be long in the land;" [*]( Exodus xx. 12.)