Exod.28.35

And it shall be upon Aaron to minister: and his sound shall be heard when he goeth in unto the holy place before the LORD, and when he cometh out, that he die not.

Exod.28.35

Aaron has to wear it when he does his priestly work. The bells will be heard when he enters the Holy Place and comes into the presence of GOD, and again when he comes out so that he won't die.

Exod.28.35

And it shall be upon Aaron when he ministers, and its sound will be heard when he goes into the holy place before the LORD and when he comes out, that he may not die.

Exod.28.35

Aaron will wear this robe whenever he enters the Holy Place to minister to the LORD, and the bells will tinkle as he goes in and out of the LORD's presence. If he wears it, he will not die.