Also see definition of "Observe" in Word Study
Study Dictionary
Observe
OBSERVE [ISBE]
OBSERVE - ob-zurv' (representing various words, but chiefly shamar, "to keep," "to watch" etc.): Properly means "to take heed to," as in Isa 42:20, "Thou seest many things, but thou observest not" and from this sense all the usages of the word in English Versions of the Bible can be understood. Most of them, indeed are quite good modern usage (as "observe a feast," Ex 12:17, etc.; "observe a law" Lev 19:37, etc.), but a few are archaic. So Gen 37:11, the King James Version "His father observed the saying" (the Revised Version (British and American) "kept the saying in mind"); Hos 13:7, "As a leopard .... will I observe them" (the Revised Version (British and American) "watch"); Jon 2:8, "observe lying vanities" (the Revised Version (British and American) "regard," but "give heed to" would be clearer; compare Ps 107:43). Still farther from modern usage is Hos 14:8, "I have heard him, and observed him" (the Revised Version (British and American) "will regard"; the meaning is "care for"); and Mk 6:20, "For Herod feared John .... and observed him" (the Revised Version (British and American) "kept him safe"). In the last case, the King James Version editors seem to have used "to observe" as meaning "to give reverence to."Observation is found in Lk 17:20, "The kingdom of God cometh not with observation" (meta paratereseos). The meaning of the English is, "so that it can be observed," but the exact force of the underlying Greek ("visibly"? "so that it can be computed in advance"?) is a matter of extraordinary dispute at the present time.
See KINGDOM OF GOD.
Burton Scott Easton
Also see definition of "Observe" in Word Study