One way to understand what Jesus taught about watching for His return is mental posturing i.e. having the right mental attitude or mid-set to meet Him when He comes. Jesus, in the gospel of Mark, describes this idea most succinctly and forcefully.

Mark 13

35 Watch ye therefore: for ye know not when the master of the house cometh, at even, or at midnight, or at the cockcrowing, or in the morning:

36 Lest coming suddenly he find you sleeping.

37 And what I say unto you I say unto all, Watch.
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