Moses
Exodus 39:21BSB·traditional attribution

Then they tied the rings of the breastpiece to the rings of the ephod with a cord of blue yarn, so that the breastpiece was above the waistband of the ephod and would not swing out from the ephod, just as the LORD had commanded Moses.

Matthew Henry Presbyterian @wholebiblehenry

In this account of the making of the priests' garments, according to the instructions given (ch. 28), we may observe, 1. That the priests' garments are called here clothes of service, Exo 39:1. Note, Those that wear robes of honour must look upon them as clothes of service; for from those upon whom honour is put service is expected.

Commenting on Exodus 39:1-31

Keil & Delitzsch Lutheran @keilanddelitzsch

Exo 39:1-31 Preparation of the priests’ clothes. - Previous to the description of the dress itself, we have a statement in Exo 39:1 of the materials employed, and the purpose to which they were devoted (“cloths of service,” see at Exo 31:10).

Commenting on Exodus 39:1-31