firefly-iii/resources/lang/pl_PL/auth.php

<?php
/**
 * auth.php
 * Copyright (C) 2016 thegrumpydictator@gmail.com
 *
 * This software may be modified and distributed under the terms of the
 * Creative Commons Attribution-ShareAlike 4.0 International License.
 *
 * See the LICENSE file for details.
 */

return [

    /*
    |--------------------------------------------------------------------------
    | 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.
    |
    */

    'failed'   => 'Te poświadczenia nie zgadzają się z naszymi danymi.',
    'throttle' => 'Zbyt wiele prób logowania. Spróbuj ponownie za :seconds sekund.',

];