(35) And his sound shall be heard.--Rather, that its sound may he heard. The great object of the bells was to make known to the people, by a sensible manifestation, every movement of their representative, every act that he performed on their behalf. The bells enabled them to follow in their thoughts the entire service that he was engaged in, to join their prayers and praises with his, and offer to God a common worship. So important was this union of priest and people in the worship of God regarded, that death was denounced on the high priest who should minister in the sanctuary without this essential garment.

28:31-39 The robe of the ephod was under the ephod, and reached down to the knees, without sleeves. Aaron must minister in the garments appointed. We must serve the Lord with holy fear, as those who know they deserve to die. A golden plate was fixed on Aaron's forehead, engraven with Holiness to the Lord. Aaron was hereby reminded that God is holy, and that his priests must be holy, devoted to the Lord. This must appear in their forehead, in open profession of their relation to God. It must be engraven like the engravings of a signet; deep and durable; not painted so as to be washed off, but firm and lasting; such must our holiness to the Lord be. Christ is our High Priest; through him sins are forgiven to us, and not laid to our charge. Our persons, our doings, are pleasing to God upon the account of Christ, and not otherwise.And it shall be upon Aaron to minister,.... That is, the robe before described shall be put upon him, that he might minister in the priest's office, for without this, as well as the other garments, he might not:

and his sound shall be heard when he goeth in unto the holy place before the Lord, and when he cometh out; by means of which the priests would have notice that they might depart, and he be alone in his ministrations; or rather, that the people might know his going out and coming in, and so give themselves up to prayer, while he was offering incense, see Luke 1:9 though the instance of Zacharias is not of an high priest, but of a common priest:

that he die not the Targum of Jonathan adds, with flaming fire. This is added, to make him, and all succeeding priests, careful that this robe, nor any other of the priestly garments, were wanting, when they ministered before the Lord; should any be wanting, it would be highly resented by the Lord: and such an one would be in danger of being cut off by death from the immediate hand of God, as Nadab and Abihu were for offering strange fire to the Lord; for, according to the Jewish writers (e), a priest not rightly attired, either with more or fewer garments than he should have, his service was illegal, and he was as a stranger, and his service strange service, unacceptable to God, yea, provoking to him; and so Jarchi on the text says, if he wanted one of these garments, he was guilty of death by the hand of heaven, the immediate hand of God.

(e) Maimon. Cele Hamikdash, c. 10. sect. 4, 5.