Matthew a disciple of Christ while writing to his Jewish audience about the old prophecy concerning the coming of their Messiah paints a picture in the passage of God's faithfulness.
Man in his sinful state could never hope to become holy as per God's unachievable standards. The mystery of being godly or holy lies in the Incarnate Christ and the Incarnate Christ in us , the Hope of Glory . Col 1:27. This is the mystic secret hidden from ages but now revealed to us.
Paul depicts this in 1 Timothy 3 :16 And without controversy great is the mystery of godliness:
God was manifested in the flesh,
Justified in the Spirit,
Seen by angels,
Preached among the Gentiles,
Believed on in the world,
Received up in glory.
Jesus Christ is also Immanuel, the only God who cares to walk with us. Amen. JP