Does Every Person Have a Right to His Own Belief?

Are we talking in man's terms or in God's terms? Man might say that we have a right to believe whatever doctrine we choose. But God says differently. "And if ye shall despise my statutes . . I also will do this unto you; I will even appoint over you terror, consumption, and the burning ague, that shall consume the eyes, and cause sorrow of heart . . (Leviticus 26:15-16)"

Adam & Eve couldn't make their own rules!
Adam & Eve existed in a literal heaven on earth with God until the first sin was committed. This is when they (and all humans through them) were cursed via the Adamic Covenant (Genesis 3:15). Adam & Eve had to give in to God's commands.

Paul couldn't either.
Paul honestly thought that it was his scriptural duty to become a Pharisee, oppose Christ, and murder Christians. He stated in Acts 26:9, "I verily thought with myself that I ought to do many things contrary to the name of Jesus of Nazareth." Even though he did this with a good conscience (Acts 23:1), it didn't make it right. Paul had to learn and obey the truth to be saved (Acts 22:16).

One Lord, One Faith, One Baptism
Read Ephesians 4:4-6. It teaches that there is one body (or church) . . one Spirit . . one hope . . one Lord, one Faith, one Baptism . . one God and Father of all. That doesn't leave many alternate choices. Any other belief can only be a fake belief in a fake God. This was the case of the Israelites and the golden calf in Exodus 32.

"For of him, and through him, and to him, are all things: to whom be glory forever. Amen (Romans 11:36)." God is the source of all things(of him), the channel of all things(through him), and the goal of all things(to him). The only reasonable response to this is to worship God and God alone.