So in this game there is a line about how some object is called a dragon egg and inside it seems there are these magic items that god placed inside. The part of the sentence that I do not get is お使いになられた. お使い is a messenger and なられた is the passive form of なる. It sounds like the magic items became the messenger. Maybe I am misunderstanding the use of the passive verb here. Could someone clarify that section this to me?
あれは竜の卵と呼ばれるもので中に神さまがお使いになられた魔法の品が入っておるそうな。