First John 4:11–19 is the backbone of John’s letter. The primary way Christians are to be recognized is by love. This is not merely what we feel, but what we do for others. True, godly love is the most powerful evidence of being ”born again” as a child of God. This love comes from God, who loved us before we loved Him. When we live in obedience to God, according to love, we can be confident in our relationship with Him, and have no need to fear His judgment.
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“1 John 4:15” Bibleref.com
1 John 4:15
15 If anyone acknowledges that Jesus is the Son of God, God lives in them and they in God.