Gregory of Nazianzus

I resort once again to history, and on considering the men of best repute in ancient days, who were ever preferred by grace to the office of ruler or prophet, I discover that some readily complied with the call, others deprecated the gift, and that neither those who drew back were blamed for timidity, nor those who came forward for eagerness. The former stood in awe of the greatness of the ministry, the latter trustfully obeyed Him Who called them. Aaron was eager, but Moses resisted, Isaiah readily submitted, but Jeremiah was afraid of his youth, and did not venture to prophesy until he had received from God a promise and power beyond his years.

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What is it that has induced this fear in me, that, instead of supposing me to be needlessly afraid, you may highly commend my foresight? I hear from Moses himself, when God spake to him, that, although many were bidden to come to the mount, one of whom was even Aaron, with his two sons who were priests, and seventy elders of the senate, the rest were ordered to worship afar off, and Moses alone to draw near, and the people were not to go up with him. For it is not everyone who may draw near to God, but only one who, like Moses, can bear the glory of God. Moreover, before this, when the law was first given, the trumpet-blasts, and lightnings, and thunders, and darkness, and the smoke of the whole mountain, and the terrible threats that if even a beast touched the mountain it should be stoned, and other like alarms, kept back the rest of the people, for whom it was a great privilege, after careful purification, merely to hear the voice of God. But Moses actually went up and entered into the cloud, and was charged with the law, and received the tables, which belong, for the multitude, to the letter, but, for those who are above the multitude, to the spirit.