In the big picture this verse means that it is necessary that there be a church on earth where there is reception from love and charity for the Lord and His divine nature and redemption. There must be some who accept religion and who have the Word for the connection to heaven and its wisdom to be maintained, without this Mankind would not survive, but would descend in abysmal darkness.
When there is such people there is still light from them to people who are outside the church and do not have the Word. This is part of the Teachings for the New Jerusalem on Sacred Scripture. Strange as it may seem, wherever the Word is read reverently and the Lord is worshiped because of the Word, the Lord is present along with heaven. This is because the Lord is the Word, and the Word is that divine truth that makes heaven what it is. This is why the Lord says, “Wherever two or three are gathered in my name, I am there in their midst” (Matthew 18:20).
This can be done with the Word by Europeans, Americans, Africans and people of any nation, and it helps all. The reason is all of humanity is connected spiritually in the body of Christ. In the big picture the whole of the universe and heaven is in form of Jesus, known as the Grand Man, and so all are connected and receive in a spiritual way, but it must be sincere and from the light of charity.
In a more personal way it means any group, even if it is 2 or three, reinforces the whole body of Christ. This must be so in this world, and when it is a good deed is done by all who participate in the sincere reading of the Word and love fellowship from its wisdom. Even those who are pagan or gentile receive wisdom in their own way for the sake of spiritual life and salvation, but those who do so from love of Jesus and His Word are the heart of the matter. From then light is distributed to all mankind in a spiritual way like blood and oxygen are distributed from the heart to the rest of the body.