Musannaf Ibn Abi Shaybah

It is narrated from Hazrat Darham Abu Ubaid al-Maharibi that I saw Hazrat Ali (may Allah be pleased with him) in the market when it started to rain. He stood under the shade of a Persian's tent. That Persian began to push him away. Ali (may Allah be pleased with him) was saying, "I am only standing here to avoid the rain." Later, when that Persian found out that it was Ali (may Allah be pleased with him), he began to strike his chest with his hand.