In his book A Shepherd Looks at Psalm 23, Phillip Keller talks about the day he bought the first sheep for his own flock. He recounts how his neighbor handed him a knife and said, “Well, Philip, they’re yours. Now you’ll have to put your mark on them.”
He spoke of the painful process of cutting distinctive notches into each sheep’s ear so they could be identified as his, even from a distance.
Keller then compared that to a law we read about in Exodus 21:
“If you buy a Hebrew servant, he is to serve you for six years. But in the seventh year, he shall go free, without paying anything…. But if the servant declares, ‘I love my master and my wife and children do not want to go free,’ then his master must take him before the judges. He shall take him to the door or the doorpost and pierce his ear with an awl. Then he will be his servant for life” (Exodus 21:2, 5-6).
The mark in the ear was a sign that he was now a willing servant. That’s all well and good, but what does that have to do with us today in the 21st century? Keller says,
“For the man or woman who recognizes the claim of Christ and gives allegiance to His absolute ownership, there comes the question of bearing His mark. The mark of the cross is that which should identify us with Him for all time. The question is—does it?”
Do you bear any mark of Christ on your life? Can people tell from a distance that you belong to Him? Do you recognize Jesus as your Shepherd? Are you His willing servant?
Something to think about.
 W. Phillip Keller, A Shepherd Looks at Psalm 23 (Zondervan. Kindle Edition), p. 10..