Khalid ibn al-Walid's Mistaken Attack on Banu Jadhimah

After the Conquest of Makkah, Khalid ibn al-Walid RA (a very recent convert) was sent, among several expeditions, to invite the tribe of Banu Jadhimah to Islam. Khalid had a personal grievance against this tribe from the Jahiliyyah era, since they had killed his uncle. When Khalid arrived with an armed party, some of the Banu Jadhimah assumed he had come for revenge and drew their swords; Khalid's men fought back. Other members of the tribe realized what was happening and announced their submission, but rather than saying the expected "Aslamna" (we have submitted), they used the unfamiliar phrase "Saba'na" (we have become Sabians), the term Arabs sometimes used, incorrectly, for those entering Islam. Khalid, not recognizing the phrase, did not understand they were professing Islam and continued the attack, killing a number of them. Abdullah ibn Umar RA and Abd al-Rahman ibn Awf RA, among other Companions present, refused Khalid's order to join the killing; when Khalid rebuked Abd al-Rahman for disobeying his commander, he cursed him.