Is Isa the Arabic equivalent of Jesus?

As this came up in a comment section on Michael Jackson and Islam, I'll post the information here, because we often deal with Muslims and need to know the truth accurately.

Is Isa the Arabic equivalent of Jesus?

The traditional Arabic name for Jesus is Yasu'. Until very recent times, all Arab Christians used no other name for Jesus. And even today, that is the name used by more than 99% of all Arab Christians. Just walk into any Arab Christian church, turn on Arabic Christian broadcasting, read Arabic Christian literature written for Christians. You will only find Yasu', never Esa. Only very recently (perhaps some 25 years ago) some Christians started to use the name Esa in Arabic publications written specifically for Muslims in the hope that they may more easily accept their message if they see the quranic name for Jesus instead of the traditional Christian one.[1] Nevertheless, among themselves, Arab Christians do not use Esa.

[I'll add here: This is wrong because it doesn't give distinction between Jesus and Isa and causes HUGE confusion. Besides being man-centered and not faithful to Scripture, it also gives the impression they have part of Jesus correct, when in fact they don't. Using Yesu' makes a clean break from all things Muslim for clarity and truth.The same is to be said for using "Allah" instead of God or Jehovah.-Denise]

The traditional Arabic rendering or transliteration of the original Hebrew name (Yeshua') is Yasu'.

Since Hebrew and Arabic are both Semitic languages, and they are closely related, there are certain well-known rules which sounds/letters in Hebrew correspond to which sounds/letters in Arabic. Specifically, the Hebrew letter Shin regularly turns into the Arabic letter Sin, e.g. the Hebrew word for peace, shalom, corresponds to the Arabic word salam. According to those linguistic rules and relationships between Hebrew and Arabic, Yasu' is the proper Arabic equivalent for the Hebrew Yeshua'.

Yeshua' = Yod + Shin + Waw + 'Ain
Yasu' = Ya + Sin + Waw + 'Ain

Again, the linguistically most appropriate Arabic equivalent for the Hebrew Yeshua' is Yasu'. Thus, the traditional Arabic name for Jesus is the linguistically most appropriate one. The transition from Yeshua' to Yasu' follows the common rules of phonetic changes from Hebrew to Arabic. In that sense, Yasu' is the true Arabic name of Jesus. There is nothing arbitrary about it. On the contrary, Yasu' is the natural equivalent of Yeshua'.

On the other hand, it is a long-standing mystery where Esa, the quranic name for Jesus, is coming from. Although there exist a number of theories that are more or less convincing, we will probably never know for sure.

End quote.

-Source

Also, more on the Muslim Isa versus the Biblical Jesus Christ here.

I'd like to add that it should be obvious to biblical Christians that Islam uses a different name for what they think is Jesus, simply because its a totally different Jesus and totally different God and totally different Book and totally different religion altogether.