To the second , who now stands before you , he presented a copper plate on which the name of Mahomet was engraved in seven languages , telling him never to part from his turban , which was the sign of a true believer , and he would taste the greatest of all joys ; while on the right arm of the third the dervish clasped a bracelet with the prayer that his right hand should be pure and the left spotless , so that he might never know sorrow .