A most distinct characteristic of truth and righteousness is narrowness.
In arithmetic, for example, there is only one correct answer to 2 + 2. (There are infinity minus one incorrect answers.) In geography, there is only one correct longitudinal and latitudinal identification for your present location. In human history, there is only one date for today—it has never been before and will never be again.
The spiritual world is equally narrow. There is only one narrow gate, then only one narrow way which has eternal life as its final destination.
The number of mediators between God and man is singular. There is only one (1 Timothy 2:5).
The faith (Jude 3), the doctrine of Christ (2 John 9), the gospel (Romans 1:16)—each descriptor of God’s eternally purposed plan of salvation is singular.
The body, Spirit, hope, Lord, faith, baptism, and God of Christianity (Ephesians 4:4-6)—each is singular.
The bread of life (John 6:35); the light of the world (John 8:12); the door of the sheep (John 10:7); the good shepherd (John 10:11); the resurrection and the life (John 11:25); the way, the truth and the life (John 14:6)—each is singular.
Righteous living is neither easy nor popular.
It is narrow, but it is possible.