Musannaf Ibn Abi Shayba 1:944

Ibn ‘Ulayyah narrated to us, from Ibn ‘Awn, from al-Sha’bi, who said: Shurayh said: "He incurs [a penalty of] four thousand, and he does not incur [a penalty for] a vessel of water," meaning the one who mixes [with a woman] but does not ejaculate.