Lawyers performed a variety of functions: they issued legal opinions at the request of individuals. They advised judges responsible for the administration of justice, especially lenders. They helped the praetors to draft their edicts, in which they publicly announced at the beginning of their mandate how they would exercise their functions and the formulas according to which certain procedures were carried out. Some lawyers have also held senior judicial and administrative positions themselves. Some changes occurred in Roman law when Christianity became the official religion of the empire in 395 AD. For example, marriage was only legal if the couple had received the blessing of a church priest. Divorce has become much more difficult. Emperors also banned ancient pagan religious cults. To describe the position of a person in the legal system, the Romans mainly used the term togeus. The person, unlike foreigners, could have been a Roman citizen (civitatis status), or he could have been free as opposed to slaves (libertatis status), or he could have had a certain position in a Roman family (family status), either as head of the family (pater familias) or as a lower member – alieni iuris – who lives according to the law of another.
Two types of status were senator and emperor. When the center of the empire was moved to the Greek East in the 4th century, many legal terms of Greek origin appeared in official Roman legislation.  Influence is even visible in personal or family law, which is traditionally the part of the law that changes the least. For example, Constantine began to restrict the ancient Roman concept of patria potestas, the power that the male head of family holds over his descendants, recognizing that the people of Potestate, the descendants, could have property rights. He apparently made concessions to the much stricter concept of paternal authority under Greek Hellenistic law.  The Codex Theodosianus (438 AD) was a codification of Constantian laws. Later, the emperors went even further until Justinian finally decreed that a child of Potestate would become the owner of everything he acquired, unless he acquired something from his father.  Between 201 and 27 BC. Approximately AD, we can see the development of more flexible laws that meet the needs of the time.
In addition to the old and formal ius civile, a new legal class is created: the ius honorarium, which can be defined as “the law introduced by judges who had the right to issue edicts to support, supplement or correct the existing law”.  With this new law, the old formalism is abandoned and new, more flexible principles of ius gentium are used. Before the Twelve Tablets (754-449 BC), private law included Roman civil law (ius civile Quiritium), which applied only to Roman citizens and was related to religion; poorly developed, with attributes of strict formalism, symbolism and conservatism, for example the ritual practice of mancipatio (a form of sale). The jurist Sextus Pomponius said: “At the beginning of our city, people began their first activities without fixed law and without fixed rights: all things were governed despotically by kings.  It is believed that Roman law is rooted in Etruscan religion and emphasizes ritual.  A father`s absolute power over his family lasted until his death. His children, although they had grown up, could not own property because the father legally owned all the property of family members. Nor could children marry without the father`s consent. Around 80 BC J.-C., towards the end of the Republic, the government creates jury trials specialized in certain crimes. Each court had a presiding judge and up to 75 jury members chosen by lot to decide a case.
At first, only patrician senators could serve as jurors, but later juries included men of other possessive classes. The first 250 years of the present era are the time when Roman law and jurisprudence reached their highest degree of sophistication. The law of this period is often called the classical period of Roman law. The literary and practical achievements of the jurists of the time gave Roman law its unique form. As the Roman Republic became an empire, its rulers faced the growing challenge of governing an increasingly diverse and distant population.