מדרש על במדבר 19:8

4) "and he shall cleanse him": through those things that are done upon his body, (viz. sprinkling, shaving, and bathing). I might think that his cleansing is thus consummated; it is, therefore, written "and he shall send," "and he shall shave," "and he shall wash," "and he shall bathe." I might think that they are all indispensable to his cleanliness; it is, therefore, written (here, after sprinkling): "and he shall cleanse him, and (after sending, washing, shaving, and bathing) (Bamidbar 19:8): "and he shall be clean." Just as the first cleansing relates to what is performed upon his body (i.e., the sprinkling), so the second relates to what is performed upon his body (i.e., the shaving and the bathing, and not the sending of the bird and the washing of his clothes.)