First Catechism
FCQ 28. What is sin? Any thought, word or deed that breaks God's law by omission or commission.
Westminster Shorter Catechism
SCQ 20. Did God leave all mankind to perish in the estate of sin and misery? God, having out of his mere good pleasure, from all eternity, elected some to everlasting life, did enter into a covenant of grace to deliver them out of the estate of sin and misery, and to bring them into an estate of salvation by a Redeemer.
http://olympiabp.blogspot.com/2013/11/memory-work-this-weeks-catechism_18.html
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