In the two weeks leading up to Christmas according to the Julian calnedar, the Church remembers the "Holy Forefathers" of Jesus Christ; in other words, the Old Testament Saints who preceded Christ in the flesh, prophesized His coming, or prefigured Him. In iconography, the Old Testament Saints can appear by themselves, in scenes from their lives, or - like here - in anachronistic compositions.
Forefathers' icon:
1 – 5: left to right: Adam, Enoch, Patriarch Abraham (holding a child symbolizing the promise made to him), Isaac (hands raised as sign of humanity) and Abraham’s grandson Jacob (holding a cloth containing his twelve sons: the Twelve Tribes of Israel).
6 – 10: left to right: Jeremiah (holding a scroll of his own prophecy), Prophet Elijah (or Elias in Greek, wearing a coat of animal hair), Patriarch of the Hebrews gave tithes: Melchizedek, Righteous Noah (holding the Ark of Salvation), and Zechariah (holding the seven-branched Menorah, a common liturgical ornament of the Temple, which this prophet helped to rebuild).
11 – 14: left to right: Samuel (last of the Hebrew judges, wearing a crown of authority, and holding the golden horn used to anoint the first two kings of the nation of Israel: Saul and David), Ezekiel, Elisha, and Moses.
15 – 22: left to right: Isaiah, Psalmist King David, Daniel, Three Holy Youths (Ananias, Azarias and Misael), Aaron the Levite, and Joshua.