Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates that once the Prophet Muhammad (peace be upon him) saw a man standing in the sun while delivering a sermon. The Prophet (peace be upon him) inquired about him, and the people informed him that he was Abu Isra’il, who had vowed to stand and not sit, not come into the shade, to fast, and not speak to anyone. The Prophet (peace be upon him) said:“Tell him to sit down, come into the shade, and speak with others, but let him complete his fast.”