Commentaries:
Barnes' Notes
Phinehas - He was marked out as the fitting director of the expedition by his conduct (compare Numbers 25:7-13) in the matter of Zimri and Cozbi.
With the holy instruments, and the trumpets - Or rather, "with the holy instruments, to wit, the trumpets," for the trumpets themselves seem to be the instruments intended.
Other Barnes' Notes entries containing Numbers 31:6:
Leviticus 25:44-46
Numbers 25:11
Deuteronomy 20:2
Psalms 98:6
DISCLAIMER: Church of the Great God (CGG) provides these resources to aid the individual in studying the Bible. However, it is up to the individual to "prove all things, and hold fast to that which is good" (I Thessalonians 5:21). The content of these resources does not necessarily reflect the views of CGG. They are provided for information purposes only.