Musannaf Ibn Abi Shayba 1:1263

Ibn Fudayl narrated to us, from Layth, from Mujahid, who said: "Whoever among you is able to spend the night in a state of purity, remembering [Allah], and seeking forgiveness for his sins, let him do so. For it has reached us that the souls are resurrected upon the state in which they were taken."