Cele mai multe lucruri care se știu despre Ioan Moshu reies indirect din [[Limonariu]].
Data nașterii sale nu este cunoscută, dar este situată între 550 și 570<ref>Vincent Déroche, "Introduction"; în: Jean Moschos, ''Le pré spirituel'', Ed. Migne, Paris, 2006, p.11.</ref> în Aigai (Cilicia)<ref>''Limonariu'', cap. 171</ref>.
He was given the epithet "''ὁ ἐγκρατής''" ("''The Abstemious''"). He lived successively with the monks at the [[ monastery of St. Theodosius]] (now Deir Dosi) in [[ Jerusalem]] , among the hermits in the [[ Jordan Valley (Middle East)| Jordan Valley]], and in the [[ New Lavra]] of [[ Sabbas the Sanctified| St. Sabbas]] near [[ Thekoa]] south - east of [[ Bethlehem]] .
About the year 578 he went to Egypt with [[Sophronius of Jerusalem|Sophronius]] (afterwards [[Greek Orthodox Patriarch of Jerusalem|Patriarch of Jerusalem]]) and came as far as the [[Great Oasis]] of the [[Libyan Desert]]. After 583 he came to [[Mount Sinai]] and spent about ten years in the [[Lavra]] of Aeliatae; he then visited the monasteries, near Jerusalem and the Dead Sea. In 604 he went to [[Antioch]] but returned to Egypt in 607. Later he came to [[Cyprus]] and in 614-615 to [[Rome]] where he died in 619.
On his deathbed he requested Sophronius to bury him, if possible, on Mt. Sinai or else at the monastery of St. Theodosius in Jerusalem. Mt. Sinai being then invaded by the Saracens, Sophronius buried him in the monastery of St. Theodosius.
John Moschus' feast day in the [[Eastern Orthodox Church]] is shared with Sophonius' ([[11 martie]])<ref>Cf. http://www.orthodoxengland.org.uk/johns.htm</ref>.
He is the author of one of the earliest hagiological works, entitled "Leimon" (''Pratum spirituale'', Spiritual Meadow), occasionally abbreviated "Prat. Spirit.". In it he narrates his personal experiences with many great [[ascetic]]s whom he met during his extensive travels, and repeats the edifying stories which these ascetics related to him.