Time is not a thing, thus nothing which is, and yet it remains constant in its passing away without being something temporal like the beings in time.

We name time when we say: every thing has its time. This means: everything which actually is, every being comes and goes at the right time and remains for a time during the time allotted to it. Every thing has its time.

Being and time determine each other reciprocally, but in such a manner that neither can the former - Being - be addressed as something temporal nor can the latter - time - be addressed as a being.

Why are there beings at all, instead of Nothing?

The human being is not the lord of beings, but the shepherd of Being.

Man is not the lord of beings. Man is the shepherd of Being.