'Is It Lawful' in the Bible

And, behold, there was a man which had his hand withered. And they asked him, saying, Is it lawful to heal on the sabbath days? that they might accuse him.

The Pharisees also came unto him, tempting him, and saying unto him, Is it lawful for a man to put away his wife for every cause?

Tell us therefore, What thinkest thou? Is it lawful to give tribute unto Caesar, or not?