diff --git a/src/parser.js b/src/parser.js
index 9c7c909..31202b9 100644
--- a/src/parser.js
+++ b/src/parser.js
@@ -512,7 +512,7 @@ class Juicescript_parser {
 		
 		// make sure this scope exists
 		if(!Object.keys(this.tree.scope).includes(this.scope)){
-			throw "unknown scope " + this.scope;
+			throw "unknown scope '" + this.scope + "'";
 		}
 		
 		// return scope
diff --git a/src/runner.js b/src/runner.js
index f87e473..aad3ffb 100644
--- a/src/runner.js
+++ b/src/runner.js
@@ -114,7 +114,7 @@ class Juicescript_runner {
 		
 		// make sure this scope exists
 		if(!Object.keys(this.tree.scope).includes(this.scope)){
-			throw "unknown scope " + this.scope;
+			throw "unknown scope '" + this.scope + "'";
 		}
 		
 		// return scope