God has first loved us and He has dealt with our sins in and through Jesus Christ. By His grace and mercy, our sins have been taken away. His love should arouse in us a wonder at the magnitude of his generosity such that we can’t do anything else but love one another. God's love generates love in us for others. No one having seen the cross and received God’s immeasurable and unmerited love displayed there can go back to a life of selfishness.
Being loved by God is the greatest gift in the world. God loves us with a perfect love. As objects of his love, we are completely undeserving. The supreme manifestation of the love of God towards us is not our present circumstances, but rather the immovable, eternal work of Christ sacrificing his life on behalf of sinners. In doing so, Jesus secured for us not only forgiveness, but righteousness and eternal life.
We live in an age of confusion and falsehood. False teachers and prophets all claim to be from God or speak for God and seek to lead many astray. John teaches the church that we must be discerning. We should not believe every one who claims a revelation from God, but rather we should test their words and their confession. The Holy Spirit aids us in our discernment and enables us to know truth from error.
Christians are to live counter-culturally. This does not mean that Christians are to be weird, or practice strange rituals - but Christians are to live a life of generosity, continuously looking for ways to help others. With Christ as our example, how do we set aside our own needs and desires and work first for the betterment of our brothers and sisters in Christ? While John does not give us a magic formula, he does let us know how Christians should discipline ourselves to act, and the power of the Holy Spirit in helping us know if we’re heading in the right direction.
Having been born again and come to faith in Christ, Christians are commanded to love one another. Within the household of faith, there are to be bonds of unity, commitment and self-sacrificial love. Just as our nature has been transformed by being born again by the Holy Spirit, so too our relationships are to be transformed following the example of Christ. Our love for our fellow brothers and sisters in Christ cannot be cheap, flimsy and fake. Rather, genuine love is distinguished by its concern for the welfare of others. Love means readiness to do anything for other people, even being prepared to give up one’s own life in order that others may live.