Be sure your sin will find you out.

-Bible (Old Testament)
Numbers 32:23.

He that is surety for a stranger shall smart for it: and he that hateth suretiship is sure.

-Bible (Old Testament)
Proverbs11:15.

The only reason so many people showed up at his funeral was because they wanted to make sure he was dead.

-Goldwyn, Sam(uel) originally  Schmuel Gelbfisz
Of Louis B Mayer.  Attributed.

God's mill grinds slow, but sure.

-Herbert, George
Jacula Prudentum (published posthumously,1651).