# Your eye is the lamp of the body

"Your eye is like the lamp of your body" or "your eye is like a lamp for  you'

# When your eye is good

"When your vision is good" or "when you see well"

# the whole body is filled with light

"the light will fill your whole body" or "you will be able to see everything clearly"

# your body is full of darkness

"you will not be able to see anything"