Musannaf Ibn Abi Shaybah 35645 — Treachery in safe conduct

It is narrated from Sulaym that there was a ceasefire treaty between Sayyiduna Mu'awiyah (may Allah be pleased with him) and the Romans. Sayyiduna Mu'awiyah (may Allah be pleased with him) advanced toward their territory so that when the term of the treaty ended he could launch a surprise attack on them. Suddenly, from one side of the army, a man came saying: "Wafa' la ghadr: fulfil the covenant and do not betray." He was Sayyiduna Amr bin Abasah (may Allah be pleased with him). He said: I heard the Messenger of Allah (peace and blessings be upon him) say: "Whoever has a treaty with a people, let him neither tie its knot nor untie it until the appointed term has fully passed, or let him throw their treaty back to them on equal terms and so end it."