Verses with the word ministry in the Old Testament (4 verses):

Numbers 4:12
And they shall take all the instruments of ministry, wherewith they minister in the sanctuary, and put them in a cloth of blue, and cover them with a covering of badgers' skins, and shall put them on a bar:

Numbers 4:47
From thirty years old and upward even unto fifty years old, every one that came to do the service of the ministry, and the service of the burden in the tabernacle of the congregation.

2 Chronicles 7:6
And the priests waited on their offices: the Levites also with instruments of musick of the LORD, which David the king had made to praise the LORD, because his mercy endureth for ever, when David praised by their ministry; and the priests sounded trumpets before them, and all Israel stood.

Hosea 12:10
I have also spoken by the prophets, and I have multiplied visions, and used similitudes, by the ministry of the prophets.