The testimony of the Angels is reported to us in scripture by Mary, the Mother of Jesus.  Mary tells us that the Angel Gabriel told her she would give virgin birth to the Messiah.  Mary reported what the shepherds told her that the angels had said to them on the night Jesus was born.  Mary told us what the angel of God said to her betrothed, Joseph, that Mary was pregnant with the Messiah by reason of the Holy Spirit and that she was still a virgin.  And she waited 50-years to be able to tell her story.