Musannaf Ibn Abi Shayba 33:505

Abu Usamah narrated to us, from Abd al-Rahman ibn Yazid, he said: Al-Qasim narrated to us, from Abu Umamah, he said: "Whoever loves for the sake of Allah, hates for the sake of Allah, gives for the sake of Allah, and withholds for the sake of Allah, has indeed perfected faith."