'Ninety nine' in the Bible

What man from among you, having a hundred sheep, and losing, from among them, one, doth not leave the ninety-nine in the wilderness and go his way after the lost one, until he find it?

I say unto you - Thus, joy in heaven, will there be, over one sinner repenting, rather than over ninety-nine righteous persons, who indeed have, no need, of repentance.