Passage
This commandment we have from him, that he who loves God should also love his brother.
This commandment we have from him, that he who loves God should also love his brother.
1 John 4:19 We love him, because he first loved us.
1 John 4:20 If a man says, “I love God,” and hates his brother, he is a liar; for he who doesn’t love his brother whom he has seen, how can he love God whom he has not seen?
1 John 4:21 This commandment we have from him, that he who loves God should also love his brother.
The verse centers on "commandment", "loves", "should", and "brother". It is saying that the verse draws attention to "commandment" and "loves", so its meaning should be read from those terms before moving to application.
The prior verse says "If a man says I love God...", giving immediate footing for "commandment" and "loves". In 1 John context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "commandment" and "loves" with trust shaped by these words, not by a vague optimism outside the passage.