Musnad Ahmad 1099:12

Abu Kamil Muzaffar ibn Mudrik narrated to us, Ibrahim ibn Sa’d narrated to us, Ibn Shihab narrated to us, from Abu al-Tufayl ‘Amir ibn Wathilah: A man passed by a group of people and greeted them with peace, and they returned the greeting to him. When he had passed them, a man among them said, "By Allah, I truly hate this man for the sake of Allah." The people of the gathering said, "By Allah, what you have said is evil. By Allah, we will surely inform him. Stand up, so-and-so," referring to one of them, "and inform him." So their messenger caught up with him and informed him of what the man had said. The man turned back until he came to the Messenger of Allah (peace and blessings of Allah be upon him) and said, "O Messenger of Allah, I passed by a gathering of Muslims among whom was so-and-so. I greeted them, and they returned the greeting. When I had passed them, a man among them caught up with me and informed me that so-and-so said, 'By Allah, I truly hate this man for the sake of Allah.' So summon him and ask him: for what reason does he hate me?" The Messenger of Allah (peace and blessings of Allah be upon him) summoned him and asked him about what the man had informed him of. He confessed to that and said, "I did say that to him, O Messenger of Allah." The Messenger of Allah (peace and blessings of Allah be upon him) said, "Why do you hate him?" He said, "I am his neighbor, and I am well-acquainted with him. By Allah, I have never seen him pray any prayer at all except this prescribed prayer which both the righteous and the wicked pray." The man said, "Ask him, O Messenger of Allah: has he ever seen me delay it from its time, or perform its ablution poorly, or perform its bowing and prostration poorly?" The Messenger of Allah (peace and blessings of Allah be upon him) asked him about that, and he said, "No." Then he said, "By Allah, I have never seen him fast at all except this month which both the righteous and the wicked fast." He said, "O Messenger of Allah, has he ever seen me break my fast during it, or diminish anything of its due?" The Messenger of Allah (peace and blessings of Allah be upon him) asked him, and he said, "No." Then he said, "By Allah, I have never seen him give to a beggar at all, nor have I seen him spend anything of his wealth in any way in the path of Allah for good, except this charity which both the righteous and the wicked perform." He said, "Ask him, O Messenger of Allah, have I ever concealed anything of the Zakat, or haggled with its collector regarding it?" He said, so the Messenger of Allah (peace and blessings of Allah be upon him) asked him about that, and he said, "No." The Messenger of Allah (peace and blessings of Allah be upon him) then said to him, "Stand up; I do not know, perhaps he is better than you."