So they gathered themselves together at Jerusalem
 By the order of Asa, ( 2 Chronicles 15:9 ) , 
 in the third month;
 of the ecclesiastical year, the month Sivan, in which month was the day of Pentecost; and that very probably was the time of their gathering: 
 in the fifteenth year of the reign of Asa;
 and which seems to be the year in which he fought the Ethiopians.