If you wish to read the texts click here: Eph 2:12-22; Lk 12:35-38
The sayings in these verses are a call to watchfulness and readiness. The call to be dressed for action would mean literally to draw up the longer outer garment and tuck it into the sash around one’s waist so as to be prepared for strenuous activity. If the servants/disciples are so ready, they will be able to be prompt in responding to the master’s knock, and will be blessed. This blessing will take the form of a reversal of roles. The master will become servant/slave. The time of the coming of the master is not known and he may come at any time, but if the servant/disciple is always ready, he/she will be blessed.
It is not difficult for us as Christians to relate to this reversal of roles, simply because our God in Jesus has already become slave. It is now left to us as servants to be ready at all times.