In 630 C.E. the Holy Prophet decided to lead an expedition to Tabuk on the Syrian border. After the victory of the Byzantines over the Persians there was the danger of the Byzantine penetration into Arabia, and the Holy Prophet wanted to forestall such a move on the part of the Byzantines, by consolidating the Muslim position on the borders.
The call to arms was given at a time when the weather was burning hot. Crops were ripe, and the people were not inclined to leave their homes before harvesting the crops. The journey was long and tedious, and many persons were averse to undertake the journey. In spite of these difficulties and setbacks, an army of thirty thousand persons was raised.
In order to finance the expedition the Holy Prophet invited contributions from his followers. Uthman made the largest contribution. He contributed one thousand diners in cash, besides a thousand camels for transport. Thc Holy Prophet greatly appreciated the services of Uthman. He gave him the tidings of paradise. He also declared that in view of this great service, Uthman was not to be judged hereafter.
The Muslim army including Uthman marched to Tabuk under the leadership of the Holy Prophet. They reached Tabuk after a weary march. There was no Byzantine army to meet the Muslims. On learning of the approach of the Muslim army, the Byzantine army had withdrawn into the interior of Syria. The Byzantine threat to invade Arabia was thus averted by the timely action on the part of the Holy Prophet. The border tribes who owed allegiance to the Byzantines transferred their allegiance to the Muslims. That made the borders safe for the Muslims.
At Tabuk, the Holy Prophet delivered an historic address he said:
"Verily the most veracious discourse is the Book of Allah. The most trusty stronghold is the word of piety.
The best of religions is the religion of Islam.
The best of precedents is the precedent of Muhammad. The noblest speech is the invocation of Allah.
The finest of the narratives is the Quran.
The best of the affairs is that which has been firmly resolved upon.
The worst in religion are those things which are created without sanction.
The best of the ways is the one trodden by the Prophets. The noblest death is the death of a martyr.
The most miserable blindness is waywardness after guidance.
The best of the actions is that which is beneficent.
The best guidance is that which is put into practice. The worst blindness is the blindness of the heart".