A Case of Idiomatic Hebrew

Here's a passage from the Sermon on the Mount that's easy to misinterpret.

Matt 6:22-23
22 The light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light.

23 But if thine eye be evil, thy whole body shall be full of darkness. If therefore the light that is in thee be darkness, how great is that darkness!
KJV

These words are basically repeated in Luke 11:34.

Here we have a couple of Hebrew idioms. The person whose eye is "single" or "good" is a good-hearted, generous person while one with an "evil" eye is stingy and selfish. This is explained by Ron Moseley in his book Yeshua.

Note the context of this part of the Sermon on the Mount beginning with 6:19. The subject is money. While "evil eye" may bring to mind the phrase in I John 2:16 "the lust of the eyes," the meaning is not the same. As Dr. Moseley mentioned in a lecture, "If God's talking about money and you're thinking lust, you're not going to get it right."

In his book, Jesus, the Jewish Theologian, Brad H, Young notes this idiom is used in the parable of the householder in Matthew 20:1-16. In v.15 the man says to a complaining laborer:

"Is it not lawful for me to do what I will with mine own? Is thine eye evil, because I am good?"

The RSV translates this last sentence as "Or do you begrudge my generosity?" Young sums up Mat 6:22-23 like this: "Or to put it another way, while inner light leads to loving one's neighbor, inner darkness leads to illiberality and niggardliness."

The evil eye idiom was around a long time, going back to Moses' day. It's used in Deut 15:9 with, obviously, the same meaning.

Deut 15:9
9 Beware that there be not a thought in thy wicked heart, saying, The seventh year, the year of release, is at hand; and thine eye be evil against thy poor brother, and thou givest him nought; and he cry unto the Lord against thee, and it be sin unto thee.
KJV