Paisi’s name day is June 19, the feast of Paisius the Great.
Churches that follow the Old (Julian) Calendar keep the same feast on July 2 of the civil calendar. See everything commemorated on June 19.
The saint behind the name
Paisius the Great
June 19, Venerable, Παΐσιος ο Μέγας
Saint Paisius was born in Egypt in the fourth century and became a disciple of Saint Pambo in Nitria together with Saint John the Short. He lived in extreme asceticism in a cave in the desert and, tradition relates, was granted visions of Christ and the gift of foreseeing the future.
Also celebrating on June 19
These names share the feast, many of them other forms of the same name:
What to say on a name day
The Greek wish is Χρόνια Πολλά (Chronia Polla), “many years.” A call or a short message on the day is what people remember. See name day wishes you can send and what a name day is.