Ba'al Shem Tov, Terumah 3/בעל שם טוב על התורה·תרומה ג׳

1I heard from my Master [the Baal Shem Tov], in the name of Rabbi Sa’adiah Gaon, that it is appropriate to desire all kinds of material things, and through this, to come to a desire for Torah and serving G-d.Ben Poras Yosef, Vayechi, p. 85b