There is still not scripture beyond the OT. Christ having fulfilled all that was written about himself in the Law and the Prophets,
Then why do you bother to quote from the Gospels? Did the Spirit tell Paul to go to the Gentiles and Peter to the Jews?
'these are written that you may [come to] believe that Jesus is the Messiah, the Son of God, and that through this belief you may have life in his name.' It is through the 'teachings' of others that belief in the Incarnation has been handed on generation after generation, handed on from those who initially experienced the risen Jesus.