'Sheep' in the Bible

My sheep wandered through all the mountains, and upon every high hill: yea, my flock was scattered upon all the face of the earth, and none did search or seek after them.

For thus saith the Lord GOD; Behold, I, even I, will both search my sheep, and seek them out.

As a shepherd seeketh out his flock in the day that he is among his sheep that are scattered; so will I seek out my sheep, and will deliver them out of all places where they have been scattered in the cloudy and dark day.