Therefore, stay awake! For you do not know on which day your Lord will come. Be sure of this: if the master of the house had known the hour of night when the thief was coming, he would have stayed awake and not let his house be broken into. So too, you also must be prepared, for at an hour you do not expect, the Son of Man will come. "Who, then, is the faithful and prudent servant, whom the master has put in charge of his household to distribute to them their food at the proper time? Blessed is that servant whom his master on his arrival finds doing so. Amen, I say to you, he will put him in charge of all his property. But if that wicked servant says to himself, 'My master is long delayed,' and begins to beat his fellow servants, and eat and drink with drunkards, the servant's master will come on an unexpected day and at an unknown hour and will punish him severely and assign him a place with the hypocrites, where there will be wailing and grinding of teeth. (Mt 24:42-51)
Thieves still enter houses and steal things away. They enter the houses even when they are strongly protected and secured. They enter even the housed of the security men and steal away things. They are still successful in their job of stealing because they know the hour and the time when the master is away or sleeping. They are awake when the master of the house is sleeping.
Servants are appointed to do their work. They are to do their work even when the master is away. Master does go behind the worker. He has his own work to do or functions to attend. Master is not the supervisor of the workers. Master’s return is not known to the workers. When the master returns he should also find his workers doing their work diligently.
Being awake and aware of what is happening around and doing the work diligently even when the master is away are the qualities expected of workers. These qualities are need especially when the servants do not know about the return of the master or the arrival of the thief. Son of Man does not behave like the thief or the master who does inform about this arrival rather the servants are to be awake and aware of what is happening around and they should be diligent.