Longer Catechism (Orthodox) 26.529

Chapter 26 — Part III — The Ten Commandments

Section 529. Q. Why are pride and vanity referred to idolatry? A. Because the proud man values above every thing his own abilities and excellences, and so they are his idol; the vain man wishes further that others also should worship the same idol. These proud and vain dispositions were exemplified even sensibly in Nebuchadnezzar, king of Babylon, who first set up for himself a golden idol, and then ordered all to worship it. Dan. iii.