3 In 1st century Judaism and in the NT, there was the belief that the righteous get new, glorified bodies in order to enter heaven (1 Cor 15:42–49; 2 Cor 5:1–10). This transformation means the righteous will share the glory of God. One recalls the way Moses shared the Lord’s glory after his visit to the mountain in Exod 34. So the disciples saw Jesus transfigured, and they were getting a sneak preview of the great glory that Jesus would have (only his glory is more inherent to him as one who shares in the rule of the kingdom).
4 Here καί (kai) has not been translated.

In other versions

And he was transfigured before them, and his face shone like the sun, and his clothes became white as light.

There he was transfigured before them. His face shone like the sun, and his clothes became as white as the light.

He was transfigured in front of them, and his face shone like the sun; his clothes became as white as the light.

As the men watched, Jesus’ appearance was transformed so that his face shone like the sun, and his clothes became as white as light.

And he was transfigured before them, and his face shone like the sun, and his clothing became bright as the light.

And was transfigured before them: and his face did shine as the sun, and his raiment was white as the light.

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