Since God is full of mercy and love and forgiveness, the common assumption is that there are many paths or doorways to God. Surely He accepts all who are "sincere."
This sounds so noble-until you hear the words of Jesus on the subject. He was short and to the point: "The door to heaven is narrow." He went on to declare that a lot of people who think they have a ticket for eternal life will be surprised when they get turned away at heaven's gates. On another occasion Jesus called himself the door (or "gate" see John 10:7-9), meaning we find God only through Him.
Instead of complaining about there being only "one way," we should rejoice that there is a way!
Luke 13:22-30