diff --git a/src/frontends/lean/parser_cmds.cpp b/src/frontends/lean/parser_cmds.cpp
index 2a2de2ba0..b81d7269a 100644
--- a/src/frontends/lean/parser_cmds.cpp
+++ b/src/frontends/lean/parser_cmds.cpp
@@ -502,7 +502,7 @@ void parser_imp::parse_set_option() {
         name lean_id = name("lean") + id;
         decl_it = get_option_declarations().find(lean_id);
         if (decl_it == get_option_declarations().end()) {
-            throw parser_error(sstream() << "unknown option '" << id << "', type 'Help Options.' for list of available options", id_pos);
+            throw parser_error(sstream() << "unknown option '" << id << "', type 'help options.' for list of available options", id_pos);
         } else {
             id = lean_id;
         }
diff --git a/src/shell/lean.cpp b/src/shell/lean.cpp
index 65a97b0be..9be435508 100644
--- a/src/shell/lean.cpp
+++ b/src/shell/lean.cpp
@@ -185,9 +185,9 @@ int main(int argc, char ** argv) {
             signal(SIGINT, on_ctrl_c);
             if (default_k == input_kind::Lean) {
 #if defined(LEAN_WINDOWS)
-                std::cout << "Type 'Exit.' to exit or 'Help.' for help."<< std::endl;
+                std::cout << "Type 'exit.' to exit or 'help.' for help."<< std::endl;
 #else
-                std::cout << "Type Ctrl-D or 'Exit.' to exit or 'Help.' for help."<< std::endl;
+                std::cout << "Type Ctrl-D or 'exit.' to exit or 'help.' for help."<< std::endl;
 #endif
                 shell sh(env, &S);
                 int status = sh() ? 0 : 1;