Commentary by Roger Oakland
The only way we can be certain we know the biblical Jesus is to know the Word of God. As Jesus Himself stated:
Abide in Me, and I in you. As the branch cannot bear fruit of itself, unless it abides in the vine, neither can you, unless you abide in Me. I am the vine, you are the branches. He who abides in Me, and I in him, bears much fruit; for without Me you can do nothing. 
In spite of clear warnings from the Scriptures we know many will be deceived into believing in “another Jesus” in the last days. These people were convinced they knew the biblical Jesus but instead had been seduced by Satan. In Jesus’ own words:
Not everyone who says to Me, “Lord, Lord,” shall enter the kingdom of heaven, but he who does the will of My Father in heaven. Many will say to Me in that day, “Lord, Lord, have we not prophesied in Your name, cast out demons in Your name, and done many wonders in Your name?” And then I will declare to them, “I never knew you…”
The very fact that Jesus never knew “them” means they never knew Him. This clearly suggests sincere “Jesus” believing people can be deceived and spend eternity in hell because they chose to believe in “another Jesus.”
Everyone knows that the Catholic Church believes in an orthodox biblical historical Jesus, born of a virgin in Bethlehem, the Son of God, the Jesus who died on a cross and was raised from the dead. How can anyone dare suggest this is not the true Jesus who can save us from our sins? However, the Catholic Church teaches that salvation was not completed by Jesus’ death on the cross. They believe each Mass is a bloodless sacrifice that requires a Catholic priest.
The apostle Paul warned about the promotion of “another Jesus.” Do you suppose this “other Jesus” he was warning about was similar to Jesus or very different? If Satan wanted to counterfeit the Jesus of the Bible, wouldn’t it be reasonable to suggest this counterfeit Jesus would be a biblical Jesus mixed together with a few characteristics that are not biblical?
Consider why Paul warned the Galatians and the Corinthians about this very danger. They had embraced the biblical Jesus, but with a twist. They had accepted the biblical Jesus but added an additional requirement for salvation. Instead of Jesus alone, it was Jesus plus works.
Paul did not hesitate to speak the truth with boldness. His rebuke was harsh:
O foolish Galatians! Who has bewitched you that you should not obey the truth, before whose eyes Jesus Christ was clearly portrayed among you as crucified?
It is important, therefore, that we be armed with a scriptural arsenal to help us identify how to discern imposters that masquerade in Jesus’ name. In Second Corinthians chapter 11, the fourth verse, Paul gave us the only answer we need to detect a counterfeit. He said: “For if he who comes preaches another Jesus whom we have not preached…”
Any Jesus that is not the Jesus according to Scripture is not the Jesus of Scripture.
 John 15:4-7
 2 Corinthians 11:4
 Galatians 3:1