Reading through Calvin's commentaries for the first time today, last chapters of Leviticus in particular

That guy gets human nature like no one else

From Lev 27: And although such careful provision was made for the Levites, yet there was scarcely any period in which they did not suffer from want, and sometimes they wandered about half-starved; nay, after the return from the Babylonish captivity, the memory of so great a blessing did not prevent a part of the tithes from being surreptitiously withheld from them; as God complains in Mal_3:8. Whence it appears that it was not without purpose that the people were so imperiously enjoined to pay them.