In each of us the energy of the Spirit is made manifest according to the measure of his faith (Romans 12:6). Therefore each of us is the steward of his own grace and, if we think logically, we should never envy another person the enjoyment of his gifts, since the disposition which makes us capable of receiving divine blessings depends on ourselves.
…Hence the person who out of jealousy envies those who practice the virtues is more than misguided, for the choice of believing and acting, and of receiving grace according to the measure of his faith, clearly depends on him and not on anybody else.
~St Maximos the Confessor