能不害怕嗎？猶太人害怕見到神的面，因為知道自己不夠聖潔，舊約中說一般情況下無人能見神的面。

Barnes 的註解：
Mat 17:6 -
They fell on their face - They entered into the cloud, or the cloud enveloped them, Luk_9:34. “They were therefore afraid.” They were awed at the presence of God, and prostrated themselves in solemn adoration on the ground, and their fears were removed only by the voice of their beloved Master. No man can see God and live; and it is only the glory of God, as it shines in the face of Christ (see 2Co_4:6), that mortals can bear.


Mat 17:1 過了六天，耶穌帶著彼得、雅各，和雅各的兄弟約翰，暗暗的上了高山，
Mat 17:2 就在他們面前變了形像，臉面明亮如日頭，衣裳潔白如光。
Mat 17:3 忽然，有摩西、以利亞向他們顯現，同耶穌說話。
Mat 17:4 彼得對耶穌說：「主啊，我們在這裡真好！你若願意，我就在這裡搭三座棚，一座為你，一座為摩西，一座為以利亞。」
Mat 17:5 說話之間，忽然有一朵光明的雲彩遮蓋他們，且有聲音從雲彩里出來，說：「這是我的愛子，我所喜悅的。你們要聽他！」
Mat 17:6 門徒聽見，就俯伏在地，極其害怕。
Mat 17:7 耶穌進前來，摸他們，說：「起來，不要害怕！」
Mat 17:8 他們舉目不見一人，只見耶穌在那裡。