Musannaf Ibn Abi Shayba 35:143

Ibn Numayr narrated to us, from Mujalid, from ‘Amir, from Jabir, who said: ‘Umar said: "I will not be brought a *muhallil* (a man who marries a divorced woman to make her lawful for her first husband) nor a *muhallal lahu* (the man for whom she is made lawful) except that I will stone them both."