diff --git a/frontend/src/components/BibleReader.tsx b/frontend/src/components/BibleReader.tsx
index 7e7cbf19..9fed28c6 100644
--- a/frontend/src/components/BibleReader.tsx
+++ b/frontend/src/components/BibleReader.tsx
@@ -269,13 +269,13 @@ const BibleReader: React.FC<BibleReaderProps> = ({ book, chapter, onBack, format
             {/* Star button - only show for authenticated users */}
             {user && verseNumber && (
               <button
-                onClick={() => toggleFavorite(verseNumber)}
+                onClick={() => verseNumber && toggleFavorite(verseNumber)}
                 className="ml-2 mt-1 p-1 rounded hover:bg-gray-200 dark:hover:bg-gray-600 transition-colors"
-                title={favorites.has(verseNumber) ? 'Remove from favorites' : 'Add to favorites'}
+                title={favorites.has(verseNumber!) ? 'Remove from favorites' : 'Add to favorites'}
               >
                 <Star
                   className={`h-4 w-4 ${
-                    favorites.has(verseNumber)
+                    favorites.has(verseNumber!)
                       ? 'text-yellow-500 fill-yellow-500'
                       : 'text-gray-400 hover:text-yellow-500'
                   } transition-colors`}