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.
In some of his last words, in Matthew 28:16-20, Jesus gave a clear mission to his disciples: to make more disciples of all people...
There are two basic principles that enable Christians with differing convictions on debatable matters to live together in harmony in the church.
When Israel reached Mount Sinai, God showed that he would provide all they needed.