Library Pseudo-Clement Recognitions
Book 1, Chapter 36: Allowance of Sacrifice for a Time.
When meantime Moses, that faithful and wise steward, perceived that the vice of sacrificing to idols had been deeply ingrained into the people from their association with the Egyptians, and that the root of this evil could not be extracted from them, he allowed them indeed to sacrifice, but permitted it to be done only to God, that by any means he might cut off one half of the deeply ingrained evil, leaving the other half to be corrected by another, and at a future time; by Him, namely, concerning whom he said himself, 'A prophet shall the Lord your God raise unto you, whom you shall hear even as myself, according to all things which He shall say to you. Whosoever shall not hear that prophet, his soul shall be cut off from his people.
English translation by Thomas Smith, in Ante-Nicene Fathers, Vol. VIII (eds. Alexander Roberts, James Donaldson, and A. Cleveland Coxe; Buffalo: Christian Literature Publishing Co., 1886). Public domain. Digital text via New Advent Church Fathers.