Hadith.1860 - The Prophet (peace be upon him and his family) said:
"If a fasting servant is insulted and responds by saying, 'I am fasting; peace be upon you. I will not insult you as you have insulted me,' the Lord (azj), Blessed and Exalted, says: 'My servant has sought refuge through fasting from the evil of My servant; I have granted him protection from the Fire.'"