'Observe' in the Bible

regularly offering burnt sacrifices to the Lord on the altar for burnt sacrifice, morning and evening, according to what is prescribed in the law of the Lord which he charged Israel to observe.

So now, in the sight of all Israel, the Lord's assembly, and in the hearing of our God, I say this: Carefully observe all the commands of the Lord your God, so that you may possess this good land and may leave it as a permanent inheritance for your children after you.