'Observe' in the Bible

He said, "Go into the city to a certain man and tell him, 'The Teacher says, "My time is near. I will observe the Passover with my disciples at your house."'"

Then some of the Pharisees began to say, "This man is not from God, because he does not observe the Sabbath." But others said, "How can a man who is a sinner perform such miraculous signs?" Thus there was a division among them.

But some from the religious party of the Pharisees who had believed stood up and said, "It is necessary to circumcise the Gentiles and to order them to observe the law of Moses."