Since the early days of the church, people have tried to deny the Incarnation and still call themselves Christians. The little letter of 2 John is an answer to them and a reaffirmation of the truth about God in the flesh.
God gave us The Ten Words, which show us how to live well and our need for Jesus Christ.
While the Old Testament is still valid, we also have the message of the one who was raised from the dead.
Christians need to walk wisely by being filled in the Holy Spirit.