First Catechism
FCQ 29. What is a sin of omission? Not being or doing what God requires.
FCQ 30. What is a sin of commission? Doing what God forbids.
Shorter Catechism
SCQ 21. Who is the Redeemer of God's elect? The only Redeemer of God's elect is the Lord Jesus Christ, who, being the eternal Son of God, became man, and so was, and continues to be, God and man in two distinct natures, and one person, forever.
http://olympiabp.blogspot.com/2013/12/memory-work-this-weeks-catechism.html
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