Similarly, (Isaiah 66:20-21) "And they will bring all your brothers from all the nations as an offering to the L–rd … And also from them will I take Cohanim and Levites, the L–rd said." And where did He say this? (Devarim 29:28) "What is concealed (from us [e.g., who is a Cohein and who, a Levite]) is known to the L–rd our G–d."