Sarantopoulou's history describes a pagan sanctuary maintained by priests who performed rituals at an altar dedicated to Athena. In AD 382, one of those priests — a man named Vrasithas — traveled to the Peloponnesian city of Patras, where he encountered Christianity. The timing was significant: the Edict of Thessalonica, issued in AD 380, had made Christianity the official religion of the Roman Empire, and it was spreading through even the most isolated corners of the Mediterranean world. Vrasithas was baptized in Patras and given the Christian name Vitalios. He returned to the temple and persuaded the other priests to convert. Tradition says they then spread Christianity through the region of Laconia. The temple of Athena became a church, initially dedicated to what the sources describe as "the birth of the Mother of God, the ever-virgin Mary." Around this church, a complex of buildings grew until, according to the historical account, it had expanded to cover approximately 200,000 square meters — a small monastic town on the mountain border.

The Taygetus range divides the Peloponnese along a spine running roughly north to south, with Laconia on its eastern flank and Messenia to the west. The monastery of Panayia Yiatrissa sits on the boundary, accessible from both sides, which gave it an importance beyond the purely spiritual. Pilgrims from the Mani and from the Messenian side of the mountains came here seeking healing, drawn by tradition of miraculous cures that Sarantopoulou's account records as central to the site's identity from early in its Christian period. Abbot Sarantopoulou noted that wars and the passage of time had erased most physical evidence from the site's early centuries — the Mani's history of conflict left little standing from before the medieval period. But the tradition of pilgrimage survived the interruptions, and the monastery was re-established formally as an Orthodox house in 1683, the date by which its current continuous existence is reckoned.

The word yiatrissa is the feminine form of yiatros, doctor or healer. Greek churches dedicated to the Virgin Mary are called Panagia — All-Holy — but the specific epithet Yiatrissa is unusual enough that it draws comment. Sarantopoulou's account offers one explanation rooted in the site's ancient past: because Athena was goddess of both healing and chastity, and because the Greek word parthenos (virgin) applied to both Athena and to Mary, the old associations of the place transferred quietly from one dedication to another. The medical meaning was already embedded in the location; the new faith adopted it. Whether or not this etymology is the whole explanation, it accounts for why a monastery on a mountain borderland became specifically associated with physical healing rather than other forms of divine intercession, and why people in pain have been climbing to this site for a very long time.

Today the monastery lies along the E4 European long-distance footpath, the trail that runs between Sparti to the east and Gytheio to the south — a route that brings walkers through Taygetus terrain past the monastery as they cross between the two sides of the range. The path makes the monastery visible to a wider traveler than the traditional pilgrim, though many who arrive on foot along the E4 find themselves pausing longer than planned. The building complex on the wooded mountainside, the tradition of healing attached to the place, and the quiet particular to mountain monasteries combine in a way that rewards unscheduled stopping.