How come Jesus said that few will enter through the narrow gate? Since all we have to do is believe that Jesus Christ died a substitutionary death for our sins, that seems pretty easy.
Entering through the narrow gate is entering by faith alone, entrusting your eternal destiny solely to the Lord . This is very difficult because by the time you know for sure whether you were correct, it will be too late to do anything about it.
Many believers add some kind of good works to their faith in an effort to have something to commend them to the Lord. They don’t realize that there is no good work sufficient to save us, and by trying to add some they’re actually telling the Lord His death wasn’t good enough for them. And once you start adding work, how do you know how much is necessary? It’s a slippery slope. It’s also the broad road that leads to the wide gate and if they don’t get off it leads to destruction.