The temporal dimension of a juridical phenomenon have constituted the object of research of the law doctrine, being analysed from more perspectives, fi rst of all, in the sense of the moment of appearance of law and of the juridical system, referring to the limit of jurisdiction which should be accepted to be within the law and minimal conditions of survival is given to the juridical system, and secondly, in the sense of diachronic perspective, of law evolution in time. The study of historical evolution of law leads to the conclusion that law is anterior to state and along its history it was and still is more than a national law. There are two minimal conditions of survival of the juridical system: a formal one, that of legitimacy, the second – teleological – promotion by means of law of the common benefit, that is, of certain morality criteria. Both conditions should be respected by modern law-maker, who cannot proclaim laws only at his will, and should proclaim laws in a stable framework– that of the Constitution.