A quote from William Gurnall on the narrowness of the path that leads to life:
Many people say a person can be saved in any religion if he just follows the light. It does not matter, they say, what you believe as long as you believe something. But their imagination is making as many roads to heaven as Scripture tells us there are ways to hell. This humanistic rationale may sound good but the end of it does not lead to Christ, who says there is no other way to life but by Him: 'I am the way, the truth, and the life' (John 14:6). John declares that anyone who will not hold the one true doctrine of Christ is marked eternally as a lost man. And he who will not take God before he dies, the devil will take as soon as he dies.~William Gurnall (The Christian in Complete Armour Volume 2, Chapter 1, Part 1).
No matter how much kindess and logic and religion a man mixes in to corrupt true doctrine, he is an obstinate sinner in God's sight and will receive the same condemnation at Christ's hands as the unrepentant drunkard or murderer.
This quote was taken from the book The Christian in Complete Armour Volume 2 - A modernized abridgement of the Puritan Classic by William Gurnall, published by Banner Of Truth.