The Book of Daniel is one of the books in the Old Testament. The prophet Daniel wrote this book around 530 B.C., recording the events during Babylonian captivity, where he and his friends became also servants of Babylonian king Nebuchadnezzar. It also records the his apocalyptic visions, actions as well as his prophesies.
The book gives a historical narrative about God protecting his faithful followers (for example, Daniel’s friends are saved from a fiery furnace, and Daniel himself is saved from being eaten by the lions) while they are in captivity. It also offers a vision hope and redemption in the future.
Daniel, in order to be faithful to the Lord, did not eat the unclean food offered to him when learning in Babylon – Daniel 1:12-16