2 Chronicles 15:10

10 They were gathered in Jerusalem in the third month of the fifteenth year of Asa's reign.

2 Chronicles 15:10 Meaning and Commentary

2 Chronicles 15:10

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.

2 Chronicles 15:10 In-Context

8 When Asa heard these words and the prophecy of [Azariah son of] Oded the prophet, he took courage and removed the detestable idols from the whole land of Judah and Benjamin and from the cities he had captured in the hill country of Ephraim. He renovated the altar of the Lord that was in front of the vestibule of the Lord's [temple].
9 Then he gathered all Judah and Benjamin, as well as those from [the tribes of] Ephraim, Manasseh, and Simeon who had settled among them, for they had defected to him from Israel in great numbers when they saw that the Lord his God was with him.
10 They were gathered in Jerusalem in the third month of the fifteenth year of Asa's reign.
11 At that time they sacrificed to the Lord 700 cattle and 7,000 sheep from all the plunder they had brought.
12 Then they entered into a covenant to seek the Lord God of their ancestors with all their mind and all their heart.
Holman Christian Standard Bible ® Copyright © 2003, 2002, 2000, 1999 by Holman Bible Publishers.  Used by permission.  All rights reserved.