Charles Ellicott Commentary Leviticus 19:28

"Ye shall not make any cuttings in your flesh for the dead, nor print any marks upon you: I am Jehovah." — Leviticus 19:28 (ASV)

Cuttings in your flesh for the dead. —It was not only the custom for mourners to let their hair grow long and wear it in a disorderly manner , but the bereaved in the East to this day make cuts and incisions in their bodies in mourning for the dead. The Israelite, however, who is created in the image of God, and who is to be as holy as the Lord is holy, must not in this way disfigure his body (Deuteronomy 14:1, and so on); he must not sorrow as others who have no hope. For transgressing this law the offender received forty stripes save one.

Nor print any marks upon you. —This, according to the ancient authorities, was accomplished by making punctures in the skin to impress certain figures or words, and then filling the cut places with stibium, ink, or some other colour. The practice of tattooing prevailed among all nations of antiquity, both among tribal peoples and civilized nations. The slave had impressed upon his body the initials of his master, the soldier those of his general, and the worshipper the image of his tutelary deity.

To prevent this disfigurement of the body which bore the impress of God’s image, and yet to display the emblem of his creed, the Mosaic Law enacted that a Hebrew should have phylacteries which he is to bind as a sign upon his hand, and as a memorial between his eyes that the Lord’s law may be in his mouth (Exodus 13:9; Exodus 13:16; Deuteronomy 6:8; Deuteronomy 11:18).