As to the date of St. Basil’s birth opinions have varied between 316 and 330.  The later, which is supported by Garnier, Tillemont, Maran, 329.  Prudent Maran, the Ben. Ed. of Basil, was a Benedictine exiled for opposing the Bull Unigenitus.  †1762. Fessler, “Natus. c. 330.” and Böhringer, may probably be accepted as approximately correct. Gregory of Nazianzus, so called, was born during the episcopate of his father, Gregory, bishop of Nazianzus.  Gregory the elder died in 373, after holding the see forty-five years.  The birth of Gregory the younger cannot therefore be put before 328, and Basil was a little younger than his friend.  (Greg. Naz., Ep. xxxiii.)  But the birth of Gregory in his father’s episcopate has naturally been contested.  Vide D.C.B. ii. p. 748, and L. Montaut, Revue Critique on Greg. of N. 1878.  It is true that Basil calls himself an old man in 374, Ep. clxii. but he was prematurely worn out with work and bad health, and to his friends wrote freely and without concealment of his infirmities.  There appears no reason to question the date 329 or 330.