'Observe' in the Bible

Blessed [is] the one who reads aloud and [blessed are] those who hear the words of the prophecy and observe the things written in it, because the time [is] near!

Therefore remember how you have received and heard, and observe [it], and repent. If therefore you are not on the alert, I will come like a thief, and you will never know [at] what hour I will come against you.