Albert Barnes Commentary Psalms 118:20

"This is the gate of Jehovah; The righteous shall enter into it." — Psalms 118:20 (ASV)

This gate of the Lord: This gate is dedicated to the service of the Lord; it is the one that belongs to the house of the Lord.

Into which the righteous shall enter: Through which the righteous pass. That is, it is for such people, and all who come with a purpose to serve and worship God should be permitted to pass through them.

I claim the privilege, therefore, of thus passing through these gates into the house of God, for I come to praise Him.

All who are truly righteous, all who desire to worship God, all who wish and purpose to be holy, have a right to enter the house of God in this way—to be recognized as His friends, to be permitted to join in all the devotions of His people.

All such will have a right to enter the temple above. No one has a right to exclude them here; no one in heaven will be disposed to exclude them there.