Charles Ellicott Commentary Exodus 13:16

"And it shall be for a sign upon thy hand, and for frontlets between thine eyes: for by strength of hand Jehovah brought us forth out of Egypt." — Exodus 13:16 (ASV)

It shall be for a token. —See the comment on Exodus 13:9. The “frontlets” (totaphôth) of this passage, and of Deuteronomy 6:8, were called tephillin in Chaldee, both words signifying properly “bands” or “circlets.” The injunctions on the subject which are here given might undoubtedly be explained as metaphorical; but those in Deuteronomy 6:6-9 seem to have been intended, and were certainly understood, literally.