Matthew 17:8

When they looked up, the only one they saw was Jesus.

Mark 9:8

And suddenly they looked all around them, but the only one they saw with them was Jesus.

Luke 9:36

And after the voice had spoken, Jesus was found alone. But the apostles kept quiet [about this incident], and did not tell anyone at that time about anything they had seen.

Acts 12:10-11

And when they passed the first two guards, they came to the iron gate leading out into the city, which opened by itself. So, they went out and, as they walked down the street, the angel [suddenly] left him.

Treasury of Scripture Knowledge

Summary

And when they had lifted up their eyes, they saw no man, save Jesus only.

Bible References

They saw

Mark 9:8
And suddenly they looked all around them, but the only one they saw with them was Jesus.
Luke 9:36
And after the voice had spoken, Jesus was found alone. But the apostles kept quiet [about this incident], and did not tell anyone at that time about anything they had seen.
Acts 12:10
And when they passed the first two guards, they came to the iron gate leading out into the city, which opened by itself. So, they went out and, as they walked down the street, the angel [suddenly] left him.