והצרוע אשר בו הנגע (תזריע יג:מה)

An apikoros (apostate who doubted the existence of Hashem), came to spend Shabbos Parshas Tazria in Belz, which was in Galicia (now in Ukraine).  When Maran Reb Yissochor Dov of Belz Zt”l was reading the Torah and reached the Passuk “והצורע אשר בו הנגע” – he raised his voice, emitting in a resounding scream.  The apikoros wasn’t fazed, and by Shalosh Seudas, Maran translated the passuk saying: “The preceding letters that make up the word צ-ר-ו-ע can be arranged to form the word הספק – the root for ספיקות – doubts.  Someone doubting Hashem’s existence is akin to a leper and will be afflicted with “הנגע” – the fleck.

And that is what happened – the apikoros was afflicted with flecks that caused him terrible pain, leaving Belz with a message for life.