Islam does not have the same God as Christianity

1. According to Muslim theology to believe that the Lord Jesus is God one has committed the unforgivable sin of "shirk".
a. Allah forgiveth not partners should be set up with him; but he forgiveth anything else, to whom he pleaseth; to set up partners with Allah is to devise a sin most heinous indeed (Sura 4:48).
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2. Muslims deny the resurrection of the Lord Jesus holding to a kind of Docetic view of the crucifixion.
That they said (in boast), "We have killed Christ Jesus the son of Mary the Messenger of Allah.; - but they killed him not, nor crucified him, but so it was made to appear to them, and those who differ therein are full of doubts, with no (certain) knowledge, but only conjecture to follow, for of a surety they killed him not (Sura 4:157).
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3. Muslims blasphemously deny the Trinity.
O people of the Book! Commit no excess in your religion; Nor say of Allah aught but the truth. Christ Jesus the son of Mary was (no more than) an apostle of Allah, and his word, which he bestowed on Mary, and a spirit proceeding from him: so believe in Allah and his apostles. Say not "Trinity"; desist; it will be better for you; for Allah is one Allah. Glory be to him: (for exalted is he) above having a son. To him belong all things in the heavens and on the earth. And enough is Allah as a disposer of affairs (Sura 4:171).
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4. Muslims hold to a "good works" salvation
then those whose balance (of good deeds) is heavy,- they will attain salvation (Sura 23:102) But those whose balances are light, will be those who have lost their souls, in Hell they will abide (Sura 23:103).