Error when instantiating model - laravel

Question

I am working on a project, using Laravel, and when I try to create a new model instance, I get 500 Internal Server Error. If I comment the "$user = new User;" line and then try redirecting to another page, it works, otherwise it just redirects me to /users and show me "Whoops, looks like something went wrong.".
This is my route:
Route::resource('users', 'UserController');
These are the create and store functions from the UserController:
public function create()
{
return View::make('register');
}
public function store()
{
$rules = array(
'name' => 'required',
'password' => 'required|confirmed',
'password_confirmation' => 'required',
'email' => 'required|email'
);
$validator = Validator::make(Input::all(), $rules);
if ($validator->fails()) {
return Redirect::to('users/create')
->withErrors($validator)
->withInput(Input::except('password'));
} else {
$user = new User; //The Error happens here
$user->name = Input::get('name');
$user->email = Input::get('email');
$user->password = Input::get('password');
$user->save();
Session::flash('message', 'Successfully created user!');
return Redirect::to('users');
}
}
This is my view:
{{ HTML::ul($errors->all()) }}
{{ Form::open(array('url' => 'users')) }}
{{ Form::label('name', 'Name') }}
{{ Form::text('name', Input::old('name')) }}
<br>
{{ Form::label('password', 'Password') }}
{{ Form::password('password', Input::get('password')) }}
<br>
{{ Form::label('password_confirmation', 'Password Confirmation') }}
{{ Form::password('password_confirmation', Input::get('password_confirmation')) }}
<br>
{{ Form::label('email', 'Email') }}
{{ Form::text('email', Input::old('email')) }}
<br>
{{ Form::submit('Submit') }}
{{ Form::close() }}
And this is my model:
<?php
class User extends Eloquent{
public static $timestamps = false;
}
I would be glad if you could help me.