'Lawful' in the Bible

Some of the Pharisees asked, "Why are you doing what isn't lawful on Sabbath days?"

How was it that he went into the house of God, took the Bread of the Presence and ate it, which was not lawful for anyone but the priests to eat, and then gave some of it to his companions?"

Then Jesus asked them, "I ask you, is it lawful to do good or to do evil on the Sabbath, to save a life or to destroy it?"

So Jesus asked the Pharisees and experts in the Law, "Is it lawful to heal on the Sabbath or not?"

Is it lawful for us to pay taxes to Caesar or not?"