'Observe' in the Bible

all things therefore whatsoever they bid you, these do and observe: but do not ye after their works; for they say, and do not.

teaching them to observe all things whatsoever I commanded you: and lo, I am with you always, even unto the end of the world.

and set forth customs which it is not lawful for us to receive, or to observe, being Romans.

Ye observe days, and months, and seasons, and years.

I charge thee in the sight of God, and Christ Jesus, and the elect angels, that thou observe these things without prejudice, doing nothing by partiality.