'Lost Sheep' in the Bible

I have gone astray like a lost sheep; seek thy servant; for I do not forget thy commandments.

My people hath been lost sheep: their shepherds have caused them to go astray, they have turned them away on the mountains: they have gone from mountain to hill, they have forgotten their restingplace.

But go rather to the lost sheep of the house of Israel.

But he answered and said, I am not sent but unto the lost sheep of the house of Israel.

What man of you having a hundred sheep, and losing one of them, does not leave the ninety-nine in the wilderness, and go after the lost sheep till he finds it.

and being come to the house, calls together the friends and the neighbours, saying to them, Rejoice with me, for I have found my lost sheep.

For you were straying like lost sheep, but now you have come back to the Shepherd and Protector of your souls.