Follow Islamic teachings, respect marriage laws in Islam .

This hadith is about a man who came to the Prophet Muhammad and told him that he was married to two sisters whom he had married during the pre-Islamic period, known as Al Jahiliyah. The Prophet advised him to go back and divorce one of them. This teaches us that it is not permissible in Islam for a man to marry two sisters at once, even if it was done before Islam was revealed. It also shows us how important it is for Muslims to follow Islamic teachings even if they were doing something different before they accepted Islam.