ctrlpanel/lang/pl/auth.php

<?php

/*
|--------------------------------------------------------------------------
| Authentication Language Lines
|--------------------------------------------------------------------------
|
| The following language lines are used during authentication for various
| messages that we need to display to the user. You are free to modify
| these language lines according to your application's requirements.
|
*/

return [
    'failed' => 'Błędny login lub hasło.',
    'password' => 'Podane hasło jest nieprawidłowe.',
    'throttle' => 'Za dużo nieudanych prób logowania. Proszę spróbować za :seconds sekund.',
];