diff --git a/prism/templates/src/diagnostic.c.erb b/prism/templates/src/diagnostic.c.erb
index 1c3114479e..12e14beb84 100644
--- a/prism/templates/src/diagnostic.c.erb
+++ b/prism/templates/src/diagnostic.c.erb
@@ -106,7 +106,7 @@ static const pm_diagnostic_data_t diagnostic_messages[PM_DIAGNOSTIC_ID_MAX] = {
     [PM_ERR_ARRAY_EXPRESSION_AFTER_STAR]        = { "expected an expression after `*` in the array", PM_ERROR_LEVEL_FATAL },
     [PM_ERR_ARRAY_SEPARATOR]                    = { "expected a `,` separator for the array elements", PM_ERROR_LEVEL_FATAL },
     [PM_ERR_ARRAY_TERM]                         = { "expected a `]` to close the array", PM_ERROR_LEVEL_FATAL },
-    [PM_ERR_BEGIN_LONELY_ELSE]                  = { "unexpected `else` in `begin` block; a `rescue` clause must precede `else`", PM_ERROR_LEVEL_FATAL },
+    [PM_ERR_BEGIN_LONELY_ELSE]                  = { "unexpected `else` in `begin` block; else without rescue is useless", PM_ERROR_LEVEL_FATAL },
     [PM_ERR_BEGIN_TERM]                         = { "expected an `end` to close the `begin` statement", PM_ERROR_LEVEL_FATAL },
     [PM_ERR_BEGIN_UPCASE_BRACE]                 = { "expected a `{` after `BEGIN`", PM_ERROR_LEVEL_FATAL },
     [PM_ERR_BEGIN_UPCASE_TERM]                  = { "expected a `}` to close the `BEGIN` statement", PM_ERROR_LEVEL_FATAL },