If it be so. — The meaning becomes clearer by omitting the word “so.” The sentence will then stand as follows: “If our God is able to deliver us... then He will do so; but if He does not deliver us, be assured that we will not serve thy gods.” The three holy children are quite content to leave the whole matter in the hands of Providence. They know that the law of obedience is the first law of all, and this they are resolved to keep. There is not the slightest ground for supposing that they expected a miraculous deliverance. Their language implies no more than faithful obedience. (See Isaiah 43:2.)
Is able. — They did not question His power; they did not know whether He would will to exercise the use of it. (Comp. Genesis 19:22.)