Musannaf Ibn Abi Shaybah

Hazrat Mujahid narrates that a man sneezed in the presence of Hazrat Ibn Umar (may Allah be pleased with them) and said: "Ashhab." Hazrat Ibn Umar (may Allah be pleased with them) said: "Ashhab is the name of Satan, which he has placed between sneezing and saying 'Alhamdulillah' so that he may be mentioned."

Hazrat Mughira says that Ibrahim considered it undesirable that when someone sneezes, it should be said: Ashhab.