God tells us the truth in that it was necessary from HIS perspective to send His own beloved Son Jesus to actually die painfully upon a cross to save anybody.
If Islam was acceptable to God or indeed any other religion then God would never have sacrificed His Son in this terrible way.
Jesus teaches us to believe on HIM!! "John 6:29 Jesus answered and said unto them, This is the work of God, that ye believe on him whom he hath sent."
"John 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life."
"John 14:6 Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me."
"John 8:24 I said therefore unto you, that ye shall die in your sins: for if ye believe not that I am he, ye shall die in your sins."
The Muslims cannot receive these teachings of Jesus. Therefore to teach the Muslim that he can be saved by Islam is a contradiction of Jesus doctrine. Therefore:: Isaiah 5:20 Woe unto them that call evil good, and good evil; that put darkness for light, and light for darkness; that put bitter for sweet, and sweet for bitter!"