Then, there is the conquest of Homs [Emessa], which took place in 14 AH. Following these events, Hazrat Abu Ubaidah (ra) advanced toward Homs, a well-known city in Syria. Homs held political significance and importance in terms of warfare as well. Homs was situated in Syria between Damascus and Aleppo. There was a large temple in Homs which people visited from far off places and many took pride in worshipping there. Nonetheless, the Byzantines wished to fight and advanced accordingly.
As a result, a great army departed from Homs and met the Muslims at Josiah, but the result was their own defeat. Hazrat Abu Ubaidah (ra) and Hazrat Khalid (ra) bin Walid besieged Homs upon their arrival. There was extreme cold weather and the Byzantines believed that the Muslims would not last long in a battle on the open battlefield. Along with this, reinforcements were also expected from Heraclius. As such, he sent reinforcements from Jazira, but they were intercepted and halted by forces sent by Hazrat Saad (ra) bin Abi Waqas, who was appointed to conquer Iraq.
(Al-Farooq, Allamah Shibli, p. 118-119, Dar al-Isha‘at, Karachi, 1991) (Yaqut Ibn Abd Allah al-Hamawi, Mu‘jam al-Buldan, Vol. 2, p.347)
Historians write that although the Byzantines had footwear made of leather, their feet would lose sensation, while the Companions (ra) and Muslims had ordinary footwear and nothing more.
(Sayyiduna Umar bin al-Khattab (ra) Shakhsiyyat aur kar namey, Muhammad Salabi,p. 734, Maktabah al-Furqan, Khangarh)
Heraclius had promised to assist the people of Homs and after encouraging them to fight, he fled to Rauha. He promised them but then left from there. The people of Homs remained in their fort. They would only fight the Muslims when it was a very cold day.
The Byzantines were in wait for aid from Heraclius and hoped that the Muslims would retreat owing to the severe cold. However, the Muslims remained resolute and the aid of Heraclius did not arrive, i.e. it did not reach the people. Furthermore, the cold weather also passed and so the people of Homs became convinced that it was impossible to challenge the Muslims. Consequently, they wished to enter into a treaty. The Muslims agreed to this and the residents were left in their homes. Like the people of Damascus, they agreed to pay the Kharaj [tax on land for non-Muslims living under Muslim rule] and the jizya [tax on non-Muslim citizens living under Muslim rule]. Hazrat Abu Ubaidah wrote to Hazrat Umar (ra) informing him about the situation. In his reply, Hazrat Umar (ra) instructed the following: “Remain there and gather all the powerful Arab tribes under your flag. Insha-Allah, I will regularly send reinforcements from here.”
(Sayyiduna Umar Farooq A‘zam, Muhammad Husain Haikal, [translated], pp. 331-332, Islami Kutub Khana, Lahore)