“Cry aloud, spare not; lift up your voice like a trumpet; tell My people their transgression, and the house of Jacob their sins.”
God’s laws are for our benefit. When we break His Commandments—when we sin (1 John 3:4)—we bring automatic penalties on ourselves. God in His mercy warns sinful humans (that’s all of us until we repent, Romans 3:23) of the curses that disobedience brings.
God works through human beings to give this warning. It is not a popular message, of course, since people don’t like to be told they are wrong. God’s messengers have often been despised and mistreated for pointing out sins, but God encourages His servants to sincerely, lovingly but powerfully give warning.
Of course, a servant of God must take the warning himself and turn from sin and not be a hypocritical messenger. He must also carry the message humbly, not arrogantly.
For more about God’s laws and the benefits of obedience and curses of disobedience, see our section on “The 10 Commandments and God’s Way of Life.”