Chronicles I 25:7

7 And the number of them after their brethren, those instructed to sing to God, every one that understood was two hundred and eighty-eight.

Chronicles I 25:7 Meaning and Commentary

1 Chronicles 25:7

So the number of them, with their brethren
Who each of them had twelve with them, as after reckoned: that were instructed in the songs of the Lord;
taught how to sing them: [even] all that were cunning;
expert and well skilled in the science of singing: was two hundred and eighty eight;
for there being twenty four classes answerable to those of the priests, and twelve in each class, twelve times twenty four makes two hundred and eighty eight.

Chronicles I 25:7 In-Context

5 All these the sons of Aeman the king's chief player in the praises of God, to lift up the horn. And God gave to Aeman fourteen sons, and three daughters.
6 All these sang hymns with their father in the house of God, with cymbals, and lutes, and harps, for the service of the house of God, near the king, and Asaph, and Idithun, and Aeman.
7 And the number of them after their brethren, those instructed to sing to God, every one that understood was two hundred and eighty-eight.
8 And they also cast lots for the daily courses, for the great and the small , of the perfect ones and the learners.
9 And the first lot of his sons and of his brethren came forth to Asaph the son of Joseph, , Godolias: the second Heneia, his sons and his brethren twelve.

The Brenton translation of the Septuagint is in the public domain.