I think one of the more horrible teachings is that people who don't believe the way you do are incapable of true love. It dehumanizes others and that makes it easier to commit injustice.
For this reason, those quotes of John are, I believe, supremely immoral.
From what I have seen, it is that people *care* about others that religion is so often rejected. All too often, religions come across as hateful and full of condemnation instead of loving and caring. That is a very good reason to reject those religions.
I can see why one can see those passages of John as immoral. I would offer one has to look beyond the verse as to what it is offering about Love. It is about the source.
It is like partaking of the heat and light of the sun. One has to be out in the midday sun on a clear day to experience the full heat and light.
So if all of us want to choose Love, what is the source? What is "true love". John is offering a source, yet the same book does also offers that we, one and all, are created with the potential of that Love within.
Is love greater than what we find in this material world? I only offer this passage as a further thought, I apologise beforehand, if you do not consider it appropriate.
"Know thou of a certainty that Love is the secret of God's holy Dispensation, the manifestation of the All-Merciful, the fountain of spiritual outpourings. Love is heaven's kindly light, the Holy Spirit's eternal breath that vivifieth the human soul. Love is the cause of God's revelation unto man, the vital bond inherent, in accordance with the divine creation, in the realities of things. Love is the one means that ensureth true felicity both in this world and the next. Love is the light that guideth in darkness, the living link that uniteth God with man, that assureth the progress of every illumined soul. Love is the most great law that ruleth this mighty and heavenly cycle, the unique power that bindeth together the divers elements of this material world, the supreme magnetic force that directeth the movements of the spheres in the celestial realms. Love revealeth with unfailing and limitless power the mysteries latent in the universe. Love is the spirit of life unto the adorned body of mankind, the establisher of true civilization in this mortal world, and the shedder of imperishable glory upon every high-aiming race and nation."
‘Abdu’l-Bahá, Selections from the Writings of ‘Abdu’l-Bahá, p. 27
Regards Tony