This is just one passage to point out an important truth: so-called "little sins" can cause great destruction. Think of a tiny screw loose inside a jet engine. That little $.15 item can cause a multi-thousand dollar engine to fail and, if it's attached to a plane, it can bring immeasurable grief to hundreds.
The warning is to treat every sin as LARGE. There really is no little sin. The devil has brought many a godly man or woman down by a "slight indiscretion" that can bring great embarrassment and spoil a wonderful ministry. Remember 1 Corinthians 10:12, "Wherefore, to him who thinks he stands, take heed, lest he fall." Watch out for the tiny pitfalls Satan will toss in your path. Tripping over a marble can fracture a skull. Doing something foolish can destroy your life.