Man and Sin by Piet Schoonenberg (1964) 2.2S
Summary of text [comment] page 72
Schoonenberg quoted 1 John 4:20. If anyone says, “I love God”, yet hates his brother, he is a liar. He who does not love his brother whom he has seen cannot love God whom he has not seen.
Is ‘love for what we see’ intrinsic to ‘the love for what we do not see’? When we love our fellow human in his deepest reality, we love him, implicitly or explicitly, in God.