Daniel is one of the four major prophets of the Old Testament, named in the Orthodox tradition alongside Isaiah, Jeremiah, and Ezekiel. By the account preserved in the synaxarion, he was a youth of the royal tribe of Judah who was carried from Jerusalem into the Babylonian captivity when Nebuchadnezzar conquered the city and destroyed the Temple, in the years following 600 BC. With three companions of like lineage he was chosen for training in the royal court and given a Chaldean name, Baltasar (Belteshazzar).
According to the tradition, Daniel and his three companions refused the king's rich food and wine, eating vegetables and drinking water, and God granted them wisdom and learning. To Daniel in particular was given the gift of insight and the interpretation of dreams and visions. He rose to prominence at the court of Nebuchadnezzar by revealing and interpreting the king's forgotten dream, and was set over a province of Babylon. He later interpreted the writing that appeared on the wall during a royal banquet, foretelling the fall of the Babylonian kingdom.
Under the Persian rulers who succeeded the Babylonians, Daniel continued in high office. The synaxarion relates that he was cast into a den of lions for his fidelity to the one living God and was preserved unharmed; the OCA account places this under Darius, while other Orthodox sources speak of his being thrown to the lions twice. His prophetic visions, recorded in the Book of Daniel, were understood by the Church to foretell the kingdom of Christ and the time of the Savior's coming, including the prophecy of the 'seventy weeks.'
Daniel is commemorated in the Orthodox Church on December 17, together with the Three Holy Youths Ananias, Azarias, and Misael, his companions in captivity. He is also remembered on the Sunday of the Holy Forefathers and the Sunday before the Nativity, among the righteous of the old covenant who awaited the Messiah.