Moses
Numbers 31:12ESV·traditional attribution

Then they brought the captives and the plunder and the spoil to Moses, and to Eleazar the priest, and to the congregation of the people of Israel, at the camp on the plains of Moab by the Jordan at Jericho.

John Gill Reformed Baptist @doctorgill

And Moses and Eleazar the priest, and all the princes of the congregation,.... Attended, no doubt, with a proper retinue: went forth to meet them without the camp; partly to do honour to them, and to congratulate them on their victory, and partly to hinder them going into the camp directly, until they were purified; see Gen 14:17.

Geneva Bible Notes Reformed @genevanotes

And they brought the captives, and the prey, and the spoil, unto Moses, and Eleazar the priest, and unto the congregation of the children of Israel, unto the camp at the plains of Moab, which [are] by Jordan [near] Jericho. (d) As the women and little children.

Keil & Delitzsch Lutheran @keilanddelitzsch

Num 31:11-12 All this booty (shalal, booty in goods), and all the prey in man and beast (malkoach), was brought by the conquerors to Moses and Eleazar and the congregation, into the camp in the steppes of Moab. In Num 31:12, שׁבי applies to the women and children who were taken prisoners, מלקוח to the cattle taken as booty, and שׁלל to the rest of the prey.

Commenting on Numbers 31:11-12