Sayyiduna Abu Layla (may Allah be pleased with him) narrates: I said to Sayyiduna Ali (may Allah be pleased with him) (the narrator says: he used to talk with Sayyiduna Ali at night; he said to him): People object to you that you come out in the summer wearing winter clothes and in the winter wearing light clothes. Sayyiduna Ali (may Allah be pleased with him) asked: Were you not with us? I replied: Yes indeed. Sayyiduna Ali (may Allah be pleased with him) said: The Prophet (peace and blessings be upon him) called Sayyiduna Abu Bakr (may Allah be pleased with him), tied a banner for him and then sent him. He set out with the people but came back in retreat. Then the Prophet (peace and blessings be upon him) called Sayyiduna Umar (may Allah be pleased with him) and tied a banner for him; he too went and then came back in retreat with the people. Then the Prophet (peace and blessings be upon him) said: "I will give the banner to a man who loves Allah and His Messenger, and Allah and His Messenger love him. Allah Almighty will grant him victory, and he is not one to flee (that is, he will not turn back)." Then the Prophet (peace and blessings be upon him) sent for me, and I came to the Prophet (peace and blessings be upon him) unable to see anything. The Prophet (peace and blessings be upon him) put his saliva in my eyes, then prayed: "O Allah, suffice him against the pain of heat and cold." (Sayyiduna Ali said:) After that, neither heat nor cold ever troubled me.
Al-Bazzar recorded it; its chain contains Muhammad bin Abd al-Rahman bin Abi Layla, who has a poor memory; the remaining narrators of this report are the narrators of the Sahih.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب المناقب / 14718