Seven of his sons, i.e. the rest of his sons, which were seven, besides David; for in all he had eight, 1 Samuel 17:12. It is true, there are but seven of them named 1 Chronicles 2:13-15, but that may be because one of them was either born of a concubine, or an obscure person; or one that died immediately after this time.
Related Commentaries of 1 Samuel 16:10
1 Samuel 16:10
10 Again, Jesse made seven of his sons to pass before Samuel. And Samuel said unto Jesse, The LORD hath not chosen these.