Knowing that time was on his side, Muhammad was in no hurry to conquer Makkah. The Treaty of Hudaybiyah was hardly more than a year old, and nothing had happened to warrant its abrogation. Being a man of his word who never failed to honor a promise, Muhammad was satisfied to return to Madinah and wait for his time in peace. During the few months that followed his return, a few skirmishes took place. He sent five men to Banu Sulaym for the sole purpose of teaching them Islam, and he endured their cold-blooded murder by their hosts. Only their leader managed to escape, and he did so purely accidentally. He also sent fifteen men to Dhat al Talh on the outskirts of al Sham in order to call its people to Islam. There, too, the messengers of Muhammad and missionaries of the faith were put to death in cold blood. The Prophet also sent some of his men to the Banu al Layth which they successfully raided, bringing back both captives and booty. He also sent a force to punish the Banu Murrah for their previous treachery. A1 Sham and the whole northern district were of particular concern to the Prophet, especially since he had already secured the south through the Treaty of Hudaybiyah and the conversion of the governor of Yaman. The Prophet looked upon the north as the gateway to the spread of Islam beyond the frontiers of the Arabian Peninsula. A1 Sham and the adjoining territories were the first object of his mission beyond Arabia. Consequently, only a few months after his return to Madinah he readied an army of three thousand fighters, some of whom had previously fought at Mu'tah, for possible deployment in the north. According to other versions, the number of the men involved was one or two hundred thousand.
Historians differ in explaining the expedition against Mu'tah. Some give the murder of Muhammad's companions at Dhat al Talh as the cause. Others relate that the Prophet had sent a messenger to the Byzantine governor of Busra, that this messenger was killed by a tribesman of Ghassan in the name of Heraclius, and that Muhammad sent this force as a punitive expedition against that governor and the empire he represented.
Just as the Treaty of Hudaybiyah was the forerunner of the pilgrimage, and this in turn of the conquest of Makkah, so was the campaign against Mu'tah an introduction to Tabuk, and this, in turn, to the conquest of al Sham which took place shortly after the Prophet's death. It is immaterial whether or not the cause which led to the conquest of Mu'tah was the murder of the Prophet's messenger to the governor of Busra or that of the fifteen missionaries he had sent to Dhat al Talh. The fact is that the Prophet-May God's peace and blessing be upon him -called up in the month of Jumada I of the year 8 A.H. (629 C.E.), three thousand of his best men and appointed Zayd ibn Harithah as their leader. In the event of Zayd's fall, Ja'far ibn Abu Talib was to assume command of the army. In the event of Ja'far's death, 'Abdullah ibn Rawahah was to take his place. Khalid ibn al Walid, the recent convert from Makkah, volunteered to join this expedition in order to prove his loyalty to the new faith. The people of Madinah bid the army farewell, and Muhammad saw them off at the outskirts of the city. He commanded them not to kill any women, children, or invalids, and not to destroy either houses or trees. Together with his companions, he prayed for them: "May God be with you! May He shield you with His protection, and may He bring you back to us safe, sound, and victorious." Most of the leaders of this army thought to surprise their enemy, as the Prophet had done on previous occasions, and thus to achieve a quick victory and return home with the spoils of war. They advanced till they reached Ma'an in the territory of al Sham without knowing what lay ahead of them.
However, the news of their march preceded them. Shurahbil, Heraclius's commissioner in al Sham, mobilized all the tribes around him and sent word to Heraclius asking for more Greek and Arab armies. Some historians assert that Heraclius himself came over with his armies and camped in Ma'ab (Moab], in al Balqa', with one hundred thousand Byzantine soldiers. They also relate that another hundred thousand men joined his main force from Lakhm, Judham, al Qayn, Bahra', and Baliyy. It is also related that Theodorus, Heraclius's brother, rather than Heraclius himself, was the leader of this army. While the Muslims were at Ma'an, they heard of this mobilization, and for two days and nights they did not know what to do. One of them advised that a message be sent to the Prophet-May God's peace and blessing be upon him-informing him of the force of the enemy and asking him for more men or for other orders. This counsel was about to receive unanimous approval when `Abdullah ibn Rawahah, who was as proud and chivalrous as he was eloquent in poetry, rose and said: "0 people! By God, that which you fear might happen to you is precisely why you came here-namely, martyrdom. We Muslims do not fight either with numbers, physical strength, or material equipment. Our only power lies in this religion which God has been gracious enough to give to us. Rise to battle and march forward! One of the two greatest blessings must befall you: either victory or martyrdom." The bravery of this eloquent poet was contagious, and soon the whole army reverberated with the same war cry. Everybody approved of ibn Rawahah's counsel. They marched forward toward al Balqa' and a village called Masharif, where the Byzantine armies were encamped. When the enemy attacked, the Muslims withdrew to the village of Mu'tah which presented to them strategic advantages, and they fortified their position. It was there that the battle was fought by three thousand Muslims against soiree one or two hundred thousand of the enemy.
Upon the death of ibn Rawahah, Thabit ibn Arqam, a tribesman of Banu `Ajlan, picked up the Prophet's banner and asked the Muslims to appoint a leader. Many nominated him, but he declined. The people then asked Khalid ibn al Wa15d to assume command. Khalid accepted despite the disintegration of Muslim power and the disorganization of their ranks. Making full use of his great military experience and unique wisdom and foresight in battle, he first commanded the Muslims to reorganize their ranks and recoup their forces. He allowed only skirmishes with the enemy in order to gain time. Soon night came and the two armies disengaged until the following morning. During the night, Khalid carefully laid out his plan. He sent a number of men toward the rear deploying them in such a way as to give the impression the next morning that massive reinforcements from Madinah were arriving to join the battle. The ruse worked. Recalling their losses and the Muslims' fierce acts of war on the previous day, the Byzantines decided to abandon the battlefield. The Muslims, pleased by the withdrawal of the enemy, withdrew toward Madinah. It was a battle in which the Muslims were not victorious. Neither did they lose.