3 Bible Verses about Lost Sheep

For ye were as sheep going astray, but are now returned to the shepherd and bishop of your souls.

Verily, verily I say to you, he that entereth not by the door into the sheepfold, but climbeth up some other way, he is a thief and a robber. But he that entereth in by the door, is the shepherd of the sheep. To him the door-keeper openeth, and the sheep hear his voice, and he calleth his own sheep by name, and leadeth them out.read more.
And when he hath led forth his own sheep, he goeth before them, and the sheep follow him: for they know his voice. They will not follow a stranger, but will flee from him; for they know not the voice of strangers. This parable spake Jesus to them; but they understood not what things they were which he spake to them. Therefore Jesus said to them again, Verily, verily I say unto you, I am the door of the sheep. Whosoever are come before me, are thieves and robbers; but the sheep did not hear them. I am the door; if any one enter in by me, he shall be safe, and shall go in and out, and find pasture. The thief cometh not, but to steal, and to kill, and to destroy: I am come that they may have life, and that they may have it abundantly. I am the good shepherd: the good shepherd layeth down his life for the sheep. But the hireling, who is not the shepherd, whose own the sheep are not, seeth the wolf coming, and leaveth the sheep, and fleeth: so the wolf seizeth them, and scattereth the flock. The hireling fleeth, because he is an hireling, and careth not for the sheep. I am the good shepherd, and know my sheep, and am known of mine; (As the Father knoweth me, and I know the Father) and I lay down my life for the sheep. I have also other sheep which are not of this fold: I must bring them likewise, and they will hear my voice, and there shall be one flock, and one shepherd. Therefore doth my Father love me, because I lay down my life, that I may take it again. No one taketh it from me, but I lay it down of myself. I have power to lay it down, and I have power to take it again. This commission have I received of my Father. There was again a division among the Jews, because of these sayings. Many of them said, He hath a devil, and is mad: why hear ye him? Others said, These are not the words of one that hath a devil. Can a devil open the eyes of the blind? Now the feast of the dedication came on at Jerusalem: and it was winter. And Jesus was walking in the temple, in Solomon's portico. Then came the Jews round about him, and said to him, How long dost thou keep us in suspense? If thou be the Christ, tell us plainly. Jesus answered them, I have told you; yet ye do not believe: the works that I do in my Father's name, they testify of me. But, as I have told you, ye do not believe, because ye are not of my sheep. My sheep hear my voice, and I know them, and they follow me.

What think ye? If a man have an hundred sheep, and one of them go astray, doth he not leave the ninety and nine and go into the mountains, and seek that which is gone astray?