Moni tis Theotóku tis Pigis; Turkish name: Balıklı Meryem Ana Rum Manastiri) or simply Zoödochos Pege (Greek: Ζωοδόχος Πηγή, "Life-giving Spring") is an Eastern Orthodox sanctuary in Istanbul, Turkey.

The present church, built in 1835, bears the same dedication as the shrine erected in this place between the end of the fifth and the beginning of the sixth century.

For almost fifteen hundred years, this sanctuary has been one of the most important pilgrimage sites of Greek Orthodoxy.

The complex is protected by a high wall, and – being surrounded by Eastern Orthodox and Armenian cemeteries – lies in a green landscape.

According to historians Procopius and Cedrenus, the church was originally erected by Emperor Justinian in the last years of his reign (559-560) near a fountain of water from a holy well (Greek: ἁγίασμα, hagiasma, whence Turkish: ayazma) situated outside the walls of Theodosius II in correspondence of today's Gate of Silivri.

A female voice ordered the future Emperor to wet the eyes of the blind man with water from a nearby swamp.

[3] On 7 September 924 Tsar Simeon I of Bulgaria burned the complex, which was at once restored by Romanos I Lekapenos (r.

[5] In 1084, Emperor Alexios I Komnenos confined the philosopher John Italus to the monastery, because of his neoplatonic theories.

It is unknown whether the Byzantines restored the building before the conquest of the city in 1453 [6] Russian pilgrims of the fifteenth century do not mention the church, only the spring.

The 16th-century French scholar Pierre Gilles writes that in 1547 the church did not exist anymore, but the sick continued to attend the spring.

The sanctuary is directed by a titular bishop and is one of the most popular among the Orthodox of Istanbul, who visit it especially during the Friday after Easter[4] and on September 14.

[6] The Life-giving spring gave origin to many churches and monasteries bearing the same name in the Greek world, but most of them were erected after the end of the Byzantine Empire.

[9] According to Nikephoros Kallistos (writing in fourteenth century) the church by that time had a rectangular shape of basilica type, with a 4:3 proportion between the sides, and was partly subterranean.

[4] According to a late legend, the day of the Conquest of Constantinople a monk was frying fishes in a pan near the source.

When a colleague announced him the fall of the city, he replied that he would have believed him only if the fishes in the pan would have come back to life.

[4] The yard in front of a church is a cemetery with marble tombs – mostly of them dating to the nineteenth and twentieth century - belonging to wealthy Rûms of Istanbul.

Characteristic of this cemetery are also several gravestones with Karamanli inscriptions,[12] which constitute by far the largest surviving group in this language.