Denarius Dei
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
(Lat "God's penny.") Earnest money; money given as a token of the completion of a bargain. It differs from arrlug in this: that arrhæ is a part of the consideration, while the denarius Dei is no part of it. The latter was given away in charity ; whence the name.