The so-called exclusivity of Christianity.
Let’s look at this another way.
I receive an invitation to a party from a friend. I show up at his home at the appointed time. It could either be a fancy mansion with many wings and rooms and surrounded by a massive granite wall no one could scale without a ladder. It could also be a small one-room house with a short wooden fence even a small child could step over without trouble. It doesn’t matter. How do I announce myself? Do I run through the darkened back yard, climb the side fence, or sneak through a window? Or do I walk to the front, open the gate, and knock on the door?
Jesus is the gate to heaven. It's never locked and swings both ways. Every human has been sent an invitation to his house. It’s up to us whether or not to accept it, and arrive as any considerate person would.
Through the front door.