A 'month,' as in Genesis 29, signifies the end of an earlier state and the beginning of a following state, thus a new state. 'A month' signifies a full state.

(Odkazy: Arcana Coelestia 3814)

4924. 'And it happened as he drew back his hand' means that it concealed its own power. This is clear from the meaning of 'hand' as power, dealt with in 878, 3387, 4920, the concealment of which is meant by 'drawing back'.