Jesus's original form in its original language is read as Yehoshua in Hebrew or in Jesus's native tongue Aramaic, Yeshua, which is the same name as Joshua of the Old testament. It means "Yahweh Saves", which is fitting for Jesus's role.

When translated into Greek it is read as Iesous, which, in Latin alphabets, is written as Iesus, or in Chinese, 耶穌. "Jesus" came about because J and I is interchangeable in Latin. But the British, who is in a habit to corrupt everything that gets adopted into their culture, reads "J" (pronounce y-) as "G" (pronounce dg-), thus Iesus becomes Dgesus.

On a side note, Spanish pronounces J as H, so their Jesus is pronounced as "Hezus".

But that still doesn't explain why Christ is translated as 基督.