Watch therefore. The end will be sudden, the final separation will be then completed; be ye therefore always prepared. Few exhortations are more frequently and impressively given than this of the duty and necessity of watchfulness.
Of course, the Christian has to watch against many things—his own evil heart, temptation, the world, but most of all he must watch and be always looking for the coming of his Lord; for whether he be regarded as Redeemer, Deliverer, or Judge, he will come as a thief in the night.
What hour. Very many good manuscripts and some late editors read "on what day." This is probably the genuine reading, "hour" being an alteration derived from Matthew 24:44. What ( ποι ìᾳ) means of what kind or quality—whether sudden, immediate, or remote.