The First Commandment (1 of 10, God's Law) Thou shalt have no other gods before me.

The original Westminster Larger Catechism (1648), on the first commandment, teaches,

Question 104: What are the duties required in the first commandment?
Answer: The duties required in the first commandment are, the knowing and acknowledging of God to be the only true God, and our God; and to worship and glorify him accordingly, by thinking, meditating, remembering, highly esteeming, honoring, adoring, choosing, loving, desiring, fearing of him; believing him; trusting, hoping, delighting, rejoicing in him; being zealous for him; calling upon him, giving all praise and thanks, and yielding all obedience and submission to him with the whole man; being careful in all things to please him, and sorrowful when in anything he is offended; and walking humbly with him.

Question 105: What are the sins forbidden in the first commandment?
Answer: See http://www.swrb.com/newslett/actualNLs/WLC.htm

Question 106: What are we specially taught by these words before me in the first commandment?
Answer: See http://www.swrb.com/newslett/actualNLs/WLC.htm

And remember the Lord Jesus Christ said:

' If ye love me, keep my commandments.' (John 14:15)

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