Musannaf Ibn Abi Shaybah

It is narrated from Hazrat Aswad that Ummul Momineen Hazrat Aisha (may Allah be pleased with her) was asked about amulets for possession. In reply, she said: What do you make of this? Here is the river Euphrates near you. Let any one of you come into it, face the direction of the water's flow, and immerse himself seven times.