Access to controller in model?

How about to use Phalcon\Registry?

Firstly you should register Phalcon\Registry service in DI (in index.php for example):

$di->set('registry', function()  {
    return new Phalcon\Registry();
}, TRUE);

Controller:

$this->registry->locale = $this->request->getBestLanguages(); 

Model:

public function beforeCreate()
{
    $this->locale = $this->getDI()->getShared('registry')->locale
}

Or you can just pass a variable in the model constructor.

Controller

$model = new Model($this->request->getBestLanguages();

Model:

    public function __construct($locale = "en")
    {
        $this->locale = $locale;
    }