If you're born again, it's compulsory that you walk in love, and that love must transcend your mere talking about love into positive actions towards others. The latter part of our opening scripture in the Message translation says ", My dear children, let's just not talk about love; let's practice real love".
Practicing real love means loving your brothers and sisters in the Lord, as Christ has loved you; " he that loveth not his brother whom he hath seen, how can he love God whom he hath not seen ?" (1 john4:20). So, you actually prove your love for God and towards him in the way you show love to others especially fellow believers. If you don't actually love those for whom Jesus died, then you really don't love God.
Learn to help and give to others; genuinely care for others. Go the extra mile today to assist someone else. Never allow selfishness or self-centeredness any place in your heart. Always, at the slightest opportunity, do good to others. Remember that every little act of love or kindness you show to a fellow believerhas great reward, for you're actually doing it unto the Lord (Matthew 25:34-45)
No wonder the apostle Paul declared in 1 john 3:16; "Hereby percieve we the love of God, because he laid down his life for us: and we ought to lay our lives for the brethren"(1 john 3:16). This means we ought to love others selflessly and unconditionally as Christ has loved us.