Mark 9:2-9

And six days afterwards Jesus took Peter and James and John, and separated them apart by themselves unto a high mountain; and he was transfigured before them. And his raiment became shining, exceeding white as snow, so as no fuller on earth can white them. And there appeared unto them Elijah with Moses; and they were talking with Jesus. Then Peter answering, said unto Jesus, Master, it shall be good for us to remain here; and let us make three tabernacles: one for thee, and another for Moses, and another for Elijah. For he knew not what he was saying, for he was beside himself. And a cloud came that overshadowed them, and a voice came out of the cloud, saying, This is my beloved Son; hear ye him. And suddenly, when they had looked around, they saw no one any more, except Jesus only with themselves. And as they came down from the mountain, he commanded them that they should tell no one what things they had seen until the Son of man was risen from the dead.