Actual believers must preach to other people not to commit evil deeds!

Verses 163-166 of Chapter 7:
And ask them (O dear Prophet Mohammed - peace and blessings be upon him) of the township that was by the sea; when they used to exceed in the matter of the Sabbath - when their fish used to come swimming atop the water in front of them on the day of Sabbath and not come on the days it was not Sabbath; this is how We used to test them, due to their disobedience. And when a group among them said, "Why do you preach to a people whom Allah is going to destroy or mete out a severe punishment?" They said, "To have an excuse before your Lord, and that perhaps they may fear." And when they forgot the advices they had been given, We rescued those who forbade evil, and seized the unjust with a dreadful punishment - the recompense of their disobedience. Consequently when they rebelled against the command to refrain, We said to them, "Be apes, despised!"