God is gracious and merciful, but He is also holy and just. This means that He had to confront sin, which destroys the people He loves. Unless He turns the hearts of His people from their wicked ways, they will not only harm themselves but also miss out on His wonderful plan for their lives. Jesus is our Good Shepherd. He doesn't want any of His sheep to wander away and be devoured by the wolves.
If you are being chastised for sin, remember that it is because God loves you and wants to turn your heart back to Himself. Be grateful that God cares enough about you to want the very best for you, even if it means temporary pain, which will bring lasting blessing.