I am the good shepherd. The good shepherd lays down his life for the sheep…I am the good shepherd; I know my own sheep, and they know me, just as my Father knows me and I know the Father. And I lay down my life for the sheep.” (John 10:11, John 10:14-15 NLT)
At night, shepherds in biblical times led their sheep to lie down in a natural pen (area boxed in by bush or rock). With his own body, the shepherd would protect the sheep from wild animals and robbers.
This is what Jesus, the Good Shepherd, does for us. In sacrificing His life on the cross, He has provided the means for our protection from the evil one. In Christ, we have security knowing that He is continually watching over us.
"Jesus is the good Shepherd going before His sheep, bidding them follow Him, and ever leading them onwards with the sweet word, Come."
— Charles Haddon Spurgeon