Boyd’s Bible Dictionary:

Putting out the eye a warfare custom, especially with dangerous prisoners (Judg. 16:2121But the Philistines took him, and put out his eyes, and brought him down to Gaza, and bound him with fetters of brass; and he did grind in the prison house. (Judges 16:21); 1 Sam. 11:22And Nahash the Ammonite answered them, On this condition will I make a covenant with you, that I may thrust out all your right eyes, and lay it for a reproach upon all Israel. (1 Samuel 11:2); 2 Kings 25:77And they slew the sons of Zedekiah before his eyes, and put out the eyes of Zedekiah, and bound him with fetters of brass, and carried him to Babylon. (2 Kings 25:7)). Painting the eyelids a fashion (2 Kings 9:3030And when Jehu was come to Jezreel, Jezebel heard of it; and she painted her face, and tired her head, and looked out at a window. (2 Kings 9:30); Jer. 4:3030And when thou art spoiled, what wilt thou do? Though thou clothest thyself with crimson, though thou deckest thee with ornaments of gold, though thou rentest thy face with painting, in vain shalt thou make thyself fair; thy lovers will despise thee, they will seek thy life. (Jeremiah 4:30); Ezek. 23:4040And furthermore, that ye have sent for men to come from far, unto whom a messenger was sent; and, lo, they came: for whom thou didst wash thyself, paintedst thy eyes, and deckedst thyself with ornaments, (Ezekiel 23:40)). “Eye-service,” reluctant service (Col. 3:2222Servants, obey in all things your masters according to the flesh; not with eyeservice, as menpleasers; but in singleness of heart, fearing God: (Colossians 3:22); Eph. 6:88Knowing that whatsoever good thing any man doeth, the same shall he receive of the Lord, whether he be bond or free. (Ephesians 6:8)).

Concise Bible Dictionary:

Used symbolically for the omnipresence of God. “The eyes of the Lord are in every place” (Prov. 15:33The eyes of the Lord are in every place, beholding the evil and the good. (Proverbs 15:3)); “the eyes of the Lord are upon the righteous” (Psa. 34:1515The eyes of the Lord are upon the righteous, and his ears are open unto their cry. (Psalm 34:15); 1 Peter 3:1212For the eyes of the Lord are over the righteous, and his ears are open unto their prayers: but the face of the Lord is against them that do evil. (1 Peter 3:12): Compare 2 Chron. 16:99For the eyes of the Lord run to and fro throughout the whole earth, to show himself strong in the behalf of them whose heart is perfect toward him. Herein thou hast done foolishly: therefore from henceforth thou shalt have wars. (2 Chronicles 16:9); Zech. 4:1010For who hath despised the day of small things? for they shall rejoice, and shall see the plummet in the hand of Zerubbabel with those seven; they are the eyes of the Lord, which run to and fro through the whole earth. (Zechariah 4:10)). His eyes are also upon the wicked, and His eyes will not spare, neither will He have compassion in the day of judgment (Ezek. 5:1111Wherefore, as I live, saith the Lord God; Surely, because thou hast defiled my sanctuary with all thy detestable things, and with all thine abominations, therefore will I also diminish thee; neither shall mine eye spare, neither will I have any pity. (Ezekiel 5:11)). The eye is also used symbolically for the organ that transmits the light to the soul. If the eye is single—there being but one object (the glory of God) before the soul—the whole body is full of light; but if the eye be evil, having divers objects (as when an eye sees double), the whole body is full of darkness. And if the light (true light it may be) be darkness, how great is that darkness! A Christian in this condition may do the very things he had strongly condemned in others (Matt. 6:22-2322The light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light. 23But 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! (Matthew 6:22‑23); Luke 11:34-3634The light of the body is the eye: therefore when thine eye is single, thy whole body also is full of light; but when thine eye is evil, thy body also is full of darkness. 35Take heed therefore that the light which is in thee be not darkness. 36If thy whole body therefore be full of light, having no part dark, the whole shall be full of light, as when the bright shining of a candle doth give thee light. (Luke 11:34‑36)).

Strong’s Dictionary of Greek Words:

from a derivative of the base of 5168; an aperture, i.e. a needle's eye
KJV Usage: