He denied the divinity of Jesus Christ, not Christ. Muslims are required to believe in Jesus and his message. The idea of Jesus’ divinity is a corruption adopted by Paul’s followers. We believe his original message was of Monotheism and worship of the One God.
Now to the link you posted with the translated Ayah as follows
“Verily We granted thee a manifest victory so that Allah may forgive thee of thy sin that which is past and that which is to come, and may perfect His favour unto thee, and may guide thee on a right path”, Sura al-Fath 48:2
These verses were revealed in reference to the Treaty of Hudaybiyya in which the Prophet made peace with unbelievers of Mecca in the year 6 A.H. The Prophet had gone with only 1400 lightly armed Muslims with the intention of doing the minor pilgrimage (‘umrah). The idol-worshippers of Mecca barred them from entering Mecca; after much discussion, they agreed to a ten years peace treaty with the Prophet.
Allah described this peace treaty as a “manifest victory”. Then He goes on to explain why He gave this “manifest victory” to the Prophet. He gives three reasons: The first reason is very interesting as well as controversial.
“so that Allah may forgive (yaghfir) thee of thy sin (dhanb) that which is past and that which is to come”
The first reason, as commonly translated, seems out of place and irrelevant to the issue of the peace treaty. There is no clear connection between granting a manifest victory and forgiving of sins. Moreover, it would seem ridiculous to help a messenger to spread the word of Islam (“to submit to God’s laws”) and then grant absolute license for committing sins to that very messenger!
The best interpretation that I have seen is of ‘Allamah Taba’tabai in his al-Mizan. He goes to the literal meaning of the words:
dhanb which is commonly used for “sin” and yaghfir
which is commonly used for “forgiving”
The word dhanb is from the verb-form dhana-ba which means “to follow”; its noun form dhanab means “tail; something that follows”. So the main idea in the word dhanb is the concept of something following the other. “Sin” is known as “dhanb” because it is an act that entails evil consequence in form of Allãh’s displeasure and punishment.
The word ghafara actually means “to cover or conceal something” which also implies the meaning of protecting something. This word is used in its original meaning in our hadith literature. For example, a hadith says “Ghaffir ash-shayb bi ’l-khidhãb” which means “Cover the white hair by dyeing” or “Conceal the old age by dyeing.” “Forgiving” is known as “ghafara” because by forgiving, Allah covers the evil consequence of sins, and protects the sinner from it.
With the literal meanings of the two crucial words in the verse: dhanb and ya ghfira, the entire passage under discussion becomes more meaningful and relevant to the Treaty of Hudaybiyya. The verses would now read as follows:
Verily We granted thee [in the Treaty of Hudaybiyya] a manifest victory; so that God may **protect **you from the past and future **consequences **[of your policy with the Meccans].