NOTES for Jo1 4:20-21
Here John links love for God and love for one's neighbor into one whole. Such a link was rooted in the Torah, and it was well known to the rabbinic tradition of Gospel times. But John considers it in the context of the new, Christian revelation. For him love is not simply relations among people, as it was in pre-Christian times; for him it is inseparable from the very nature of the Kingdom. Before, love, like its opposite hatred, was above all a relation connecting people with one another, just as hatred was a relation separating people.
The environment within which relations were built remained natural, predominantly psychic. And it was the nature of the fallen world, at whose foundation lay natural energy that did not so much reveal God to a person as conceal Him. Love as a spiritual phenomenon could not avoid coming into contradiction with such God-concealing nature, and therefore in the fallen world love could not unfold in all its fullness. Where it could not penetrate, room remained for fallen nature with all its manifestations, including the fears characteristic of the psyche of fallen humanity, not always conscious but always real and always hindering a person from living a full spiritual life.
The Kingdom is another matter. Here natural energy is replaced by the energy of God's love. It is like natural energy in that it grants the possibility of being to all existing forms and manifestations of natural life. But unlike the natural energy of the fallen world, the energy of God's love does not hide God; on the contrary, it reveals Him, His will, and His presence.
Such an environment fully corresponds to relationships of love among people: spirit and nature come into complete harmony. Love can now unfold in all fullness; in the Kingdom, unlike in the untransformed world, nothing hinders it. Therefore complete deliverance from fear is possible here: the former psychic nature gives way to a new one, fully obedient to the human will. Love manifests itself in fullness, and no room for fears remains in the human soul. This is the Christian life to which John, as well as the other apostles, bore witness.