This paper is intended to examine the Islamic images of Jesus by analyzing the Qur`an and early Hadith including ascetic literatures. Understanding Jesus is one of key theological issues in Muslim-Christian relations. Most Christians emphasize the divinity of Jesus Christ, regarding him as `the Son of God` and the second person of Trinity. On the contrary, Muslims, rejecting the Christian view of Jesus totally, argue that Jesus was one of prophets to deliver the message from God and teach people the straight path to God. In Korean academia, there have been two major trends to understand Jesus religiously. First, Christian scholars as outsiders of Muslim community represent Christian response to Muslim understanding of Jesus and show missiological view to find out the common ground between Islam and Christianity. In the case of Jeon Jae Ok, she pays attention to the importance of inter-religious dialogue and mutual learning on the basis of different identities of Muslim and Christians. Second, Muslim scholars as insiders of Muslim ummah claim that Christian scriptures had been distorted and forged by followers of Jesus through the process of transmission. Son Young Ju shows us an example of Muslim understanding of Jesus as the prophet of God. Overcoming two approaches of particular religionists, the author attempts to give a religious-phenomenological explanation about the structural relations between Islam and Christianity, especially in terms of understanding Jesus in the Qur`an. Qur`anic narratives help Muslims and even Christians to have constructive and effective communications with one another in six respects: ① freedom of religion, ② humanity of prophets, ③ unity of religion, ④ universality of God`s forgiveness and judgment, ⑤ importance of praxis. In addition, major issues of differences are related to ① the authenticity of the Bible, ② gnostic influence, ③ concept of Trinity, ④ the essential Islam, ⑤ God as ultimate cause, and ⑥ variety of responses to Christ and Christians. Various images of Jesus are expressed in the Qur`an and early Hadith, including the 8th and the 9th century ascetic literatures, where Jesus is described as the prophet of God and a wandering ascetic. Muslims have created new narratives of Jesus by integrating Christian scriptures into the Qur`anic Jesus. The continuity and discontinuity between the Qur`anic Jesus and Jesus in Muslim Gospel help Muslims to expand the images of Jesus into the diversity in unity of God. The further study on Jesus` images will help the Muslim-Christian relations to improve in terms of mutual understanding and identity formation.