John Wesley on Numbers 15:22

All these commandments - Those now spoken of, which concern the outward service of God, or the rites or ceremonies belonging to it. And herein principally this law may seem to differ from that Lev 4:13, which speaks of some positive miscarriage, or doing that which ought not to have been done, about the holy things of God; whereas this speaks only of an omission of something which ought to have been done about holy ceremonies.