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We know that we have passed from death to life, because we love our brothers. Anyone who does not love remains in death.
— 1 John 3:14 · The Bible

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The writer treats love for one's brothers as proof of having crossed from death into life. Love becomes the visible sign of being truly alive. By the same logic, anyone who withholds love is described as still dwelling in death.
Context reviewed