Why We Sin

Lord's Day Three Heidelberg Catechism

6. Did God then create man so wicked and perverse? By no means; but God created man good, and after his own image, in true righteousness and holiness, that he might rightly know God his Creator, heartily love him and live with him in eternal happiness to glorify and praise him.

7. Whence then proceeds this depravity of human nature? From the fall and disobedience of our first parents, Adam and Eve, in Paradise; hence our nature is become so corrupt, that we are all conceived and born in sin.

8. Are we then so corrupt that we are wholly incapable of doing any good, and inclined to all wickedness? Indeed we are; except we are regenerated by the Spirit of God.