Q. 66. What art thou commanded in the second Commandment?
A. Not to serve God with will-worship, though it seem never so wise and humble, and mortifying (Colossians 2:23). To abhor all gross thoughts of God (Acts 17:29) as that he is such a one, as mens' selves do think him to be (Psalm 50:21). Not to make any Image (Deuteronomy 5:8) unless God should reveal a new Commandment, as once he did for Cherubims in the sanctuary (Exodus 25:18) and the brazen Serpent in the wilderness (Numbers 21:8) or unless it be in a civil use (Matthew 22:20). To abhor images of Idolaters, either to worship God before them (2 Chronicles 25:14) or in them, as the Jews did God in Baal (Hosea 2:16) or to be put in mind of God by them (Hosea 2:17) or being at Mass or communion of Service with them (1 Corinthians 10:21) or housing them (2 John 10) or bidding them God speed (2 John 11) or learning any of their devises or customs of them (Deuteronomy 12:30) or familiar reading their Books (Acts 19:19). Unless it be to confute them by their own writers (Acts 17:28) and to upbraid carnal Professors with their strictness in their kinds (Romans 2:14-17, &c.).
Q. 67. What else art thou commanded in the Second Commandment?
A. Not to lean to mine own knowledge (Proverbs 3:5) nor to serve God by the precepts of Men (Isaiah 29:13) nor as men bid me (Mark 7:6). Nor according to the Traditions and customs of the lives of our Fore-fathers (1 Peter 1:18). I am commanded to do, not only in matter what, but also in manner, as the Lord commandeth (Genesis 6:22). For otherwise my prayers and services that I do unto God, and all my sacrifices and oblations are no better then murder, or a Dog's neck, or Swine's blood, or Idolatry; so indeed it is, if I serve him after my own ways (Isaiah 66:3) not only sticks and stones are Idols (Leviticus 26:1) but carnal fancies, imaginations, dulness, deadness, luke-warmness; for there be idols in the heart (Ezekiel 14:3-4). Covetousness is Idolatry (Colossians 3:5). Stubbornness is as idolatry (1 Samuel 15:23). A careless Christian is an Idol, there is an idol Professor, an idol Christian, an idol Shepherd (Zechariah 11:17).
(Thanks to Matthew Lankford at the Idolatry Condemned blog for bringing this to my attention)