And when he came to the den, he cried with a lamentable voice unto Daniel: and the king spake and said to Daniel, O Daniel, servant of the living God, is thy God, whom thou servest continually, able to deliver thee from the lions?
O Daniel, servant of the living God - having life Himself, and able to preserve thy life; contrasted with the lifeless idols (cf. Daniel 5:23, "the gods of silver and gold, of brass, iron, wood, and stone, which see not, nor hear, nor know"). Darius borrowed the phrase from Daniel; God extorting from an idolater a confession of the truth.
Whom thou servest continually - in times of persecution as well as times of peace.
Is thy God ... able to deliver thee from the lions? - the language of doubt, yet hope.