Musnad Abu Ya'la al-Mawsili 160:188

Ahmad ibn Isa narrated to us, Abdullah ibn Wahb narrated to us, from Usamah, from Ubayd ibn Nastas, the freed slave of Kathir ibn al-Salt, who narrated to him from Sa'id al-Maqburi, from Abu Hurayrah, that the Messenger of Allah (may Allah bless him and grant him peace) said: "O people, indeed wealth is not from the abundance of worldly goods, but wealth is the wealth of the soul. And indeed, Allah, the Almighty and Majestic, will fulfill for His servant what He has written for him of provision, so be moderate in seeking it; take what is lawful and leave what is forbidden."