Gal_1:8 (KJV) But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed.
There are many references in the Word. If any man teaaches something other than the gospel of Jesus, he is a liar.
Ok, I see another who doesn't believe what the bible SAYS . Look again closely please.
6¶I marvel that ye are so soon removed from him that called you into the grace of Christ unto ANOTHER GOSPEL :
7Which is not another; but there be some that trouble you, and would pervert the GOSPEL OF CHRIST ( GOOD NEWS OF CHRIST ) .
8But though we, or an angel from heaven, preach ANY OTHER gospel unto you THAN THAT WHICH WE HAVE PREACHED UNTO YOU ( WHAT WAS PREACHED UNTO THEM ? ) , let him be accursed.
9As we said before, so say I now again, If any
man preach ANY OTHER gospel unto you THAN THAT YE HAVE RECIEVED , let him be accursed.
What your imagining it says is " There is only one good news that was ever spoken of through all time so if another comes to you and is preaching that Jesus is not God ,he didn't die on a cross ect then let him be accursed . "
Of course we should beware of those pesky J dubs but Paul is simply saying ' OTHER THAN ' ' OTHER THAN THE ONE THEY RECIEVED ' .OTHER THAN THE ONE THEY DELIVERED TO THEM.When we find the ONE they recieved then we know the difference . The one THEY recieved is not the same one they recieved in luke 9.6 nor will it be the same one they will recieve during or after the tribulation. Its false teaching when its taught the Paul means ' there is only ONE gospel.
If someone was to preach to them the Gospel back in luke 6.9 after receiving Paul's Gospel, this would also be ' another ' Gospel than the one THEY recieved .