From the Orthros service (Tone 4) which precedes the Divine Liturgy of St. Basil the Great, celebrated by the Eastern Orthodox churches on December 25, the Nativity of Christ.
Come, ye believers, let us see where Christ was born. Let us follow the star whither it goeth with the Magi, kings of the east; for there angels praise him ceaselessly, and shepherds raise their voices in a worthy song of praise, saying, Glory in the highest to the One born today in a cave from the virgin Theotokos in Bethlehem of Judaea.
Glory to the Father, and to the Son, and to the Holy Spirit.
Why wonderest thou, O Mary; and why art thou astonished in thy inner self? And she respondeth, saying, Because I have given birth in time to a Son unbound by time; nor do prehend the manner of conception of him that is born. I have known no man; how then give I birth to a son? For who hath yet seen a birth without seed? But since God willeth, the order of nature is e, as it hath been written, Christ hath been born of the Virgin in Bethlehem of Judaea.
Both now and ever and unto ages of ages. Amen.
He that all containeth not, how was he contained in the womb? And he that is in the bosom of the Father, how shall he be carried in the arms of his Mother? Verily, all this hath been fulfilled as he himself knew and willed and was pleased to do; for he that is not carnal hath e incarnate by his own choice; and he that is hath turned for our sakes to that which he was not, sharing our creation, yet inseparable from his essence, Verily, Christ hath been born with two Natures, desiring to perfect the heavenly world.