Religions are all the same in one way: they have rules. Law. Commandments you must follow.
The assumption is: This is what makes a religion true (or good).
But this assumption is wrong. We make this assumption because we actually think we can follow the rules. We are so self-righteous that we think we are able to keep the Law. Self-righteousness says all religions are the same.
Because the truth is, these commandments are impossible for us. In fact, they were not given to us to show us how to gain life. They were given to us to show us how we deserve death. How the sentence of death against mankind - every human dies - is just. It is true.
This Law in which all religions are the same is merely preparing the way for the true religion. The only religion with something OTHER than rules. And His Name is Jesus. For God so loved the world, that He gave His Only Son that whoever believes in Him should not perish but have eternal life.
The true religion has Law and Gospel. Law and Good News. Law and Mercy. Free, unconditional mercy that is revealed outside and without the constraints of the Law. What God has done for you in Christ, He did because of Himself - not because of you. He offers and gives you freedom from the Law, because He is a merciful God. Because He is the only true God.
All religions are the same because they have rules. All false religions have only rules. Only Christianity has the Good News of grace in Jesus Christ. And here's the truth: This is what makes a religion good. (and true)