Musannaf Ibn Abi Shayba 19:789

Abu Bakr narrated to us, he said: Ibn Mubarak narrated to us, from Abu Bakr ibn Abi Maryam, from Hakim ibn Umayr, he said: Umar ibn al-Khattab wrote: "Do not let the commander of an army or a detachment flog anyone with a prescribed punishment (hadd) until he reaches the border (al-darb), lest the zeal of Satan incite him to join the disbelievers."