'Liberty' in the Bible

The wife is bound by the law as long as her husband liveth; but if her husband be dead, she is at liberty to be married to whom she will; only in the Lord.

But take heed lest by any means this liberty of yours become a stumblingblock to them that are weak.

Or again, is it only Barnabas and myself who are not at liberty to give up working with our hands?

Conscience, I say, not thine own, but of the other: for why is my liberty judged of another man's conscience?