In ancient Roman religion and mythology, Janus is the god of beginnings and transitions,[1] thence also of gates, doors, doorways, endings and time. Most often he is depicted as having two heads, facing opposite directions: one head looks eastward and the other westward. Symbolically they look simultaneously into the future and the past, back at the last year and forward at the new.
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The function of god of beginnings has been clearly expressed by numerous ancient sources, among them most notably perhaps by Cicero, Ovid and Varro.[22] As a god of motion he looks after passages, causes the startings of actions, presides on all beginnings and since movement and change are bivalent, he has a double nature, symbolised in his two headed image.[23]He has under his tutelage the stepping in and out of the door of homes,[24] the ianua, which took its name from him,[25] and not viceversa.[26] Similarly his tutelage extends to the covered passages named iani, and foremostly to the gates of the city, including the cultual gate of the Argiletum, named Ianus Geminus or Porta Ianualis from which he protects Rome against the Sabins.[27] He is also present at the Sororium Tigillum, where he guards the terminus of the ways into Rome from Latium.[28] He has an altar, later a temple near the Porta Carmentalis, where the road leading to Veii ended, as well as being present on the Janiculum, a gateway from Rome out to Etruria. [29]
The connexion of the notions of beginning (principium) and movement and transition (eundo), and thence time, has been clearly expressed by Cicero.[30] In general, Janus is at the origin of time as the guardian of the gates of Heaven: Jupiter himself moves forth and back because of Janus's working.[31] In one of his temples, probably that of Forum Holitorium, the hands of his statue were postured so as to show number 355, later 365, symbolically expressing his mastership over time.[32] He presides over the concrete and abstract beginnings of the world,[33]such as religion and the gods themselves,[34] he too holds the access to Heaven and other gods: this is the reason why men must invoke him first, regardless of the god they want to pray or placate.[35] He is the initiator of the human life,[36] of new historical ages, and economical enterprises: in myth he first minted coins and the as, first coin of the libral series, bears his effigy on one face.[37]
Because of his initial nature he was frequently used to symbolize change and transitions such as the progression of past to future, of one condition to another, of one vision to another, the growing up of young people, and of one universe to another. He was also known as the figure representing time because he could see into the past with one face and into the future with the other. This is also one of the explanations of his image with two heads looking in opposite directions.[38] Hence, Janus was worshipped at the beginnings of the harvest and planting times, as well as marriages, deaths and other beginnings. He was representative of the middle ground between barbarity and civilization, rural country and urban cities, and youth and adulthood. Having jurisdiction on beginnings Janus had an intrinsic association with omens and auspices.[39]