In his Homily III on the Mother of God, Syrian Christian Jacob of Serug identified the Ancient of Days from Dan 7, not with God (the Father), but with Jesus:
“O virgin full of wonder, who grants me that you
come to me,
because your Son is the Lord and the Prime mover who
cannot be dishonoured.
“O maiden in whom the Ancient of days willed to be
carried,
how can I encompass a greeting from your lips? (Jacob of Serug, On the
Mother of God [trans. Mary Hansbury; Popular Patristic Series 19; Crestwood,
N.Y.: St. Vladimir’s Seminary Press, 1998], 80)
