The eye, lamp of the body

The majority of biblical references to the eye involve it acting as described in Job 14:3, as an organ of judgement, typically with the subject of its gaze being either good or bad in the eyes of the beholder (e.g. Josh 22:33; 2 Kgs 14:3).
The active eye

The ancient Hebrew’s concept of the eye was not quite like ours. To them, it was not so much a passive receptor, rather it was an active agent of revelation, enlightening them to the nature of the world around them and impacting their reaction to it. The opening of the eyes brings new comprehension, e.g. in Gen 3:7, where Adam and Eve only realise the consequences of eating the forbidden fruit once their eyes are opened. Hence, as Opperwall observes: “often the eye represents the total process of perception and understanding” (2002, 249).

The Hebrews portrayed the eye as a source of illumination (Ps 38:10, Pr 15:30), it cast light on things (Pr 23:5), and was likened to a truth revealing lamp (Pr 20:20, cf 2 Sam 22:28-29), a function recalled in the Sermon on the Mount (Matt 6:22-3). In 2 Enoch, which dates from between 30 B.C.E. and 70 C. E., Enoch likens the Lord’s eyes to the greatest of sources of light: “I have seen the Lord’s eyes, shining like the sun’s rays” (2 En 39 [Charles]).

Nor was this understanding, of eyes as a source of light, limited to Israelite culture, amongst the Egyptian pantheon is the sky deity Horus, whose eyes were considered to be the sun and moon (Morenz & Keep 1992, 262). A similar description is found on the third century B.C.E. Stela of Somtutefnakht (Lichtheim 1973a, 41), which extols Harsaphes: “Whose right eye is the sun-disk, Whose left eye is the moon” (Lichtheim 1973, 42). God, the ultimate truth revealer, gives light to the eyes (Pr 29:13) and the word of God enlightens them (Ps 19:8), hence king David asked God to light up his eyes so that his enemies cannot prevail (Ps 13:3). In the imagery of John’s Revelation, Jesus is portrayed, standing amidst lamp stands, with eyes that are likewise flaming sources of light (Rev 1:14). 

The relative state of the eyes was linked to physical wellbeing (Opperwall 2002, 249). For example, when Jonathan’s fatigued body was refreshed with honey, it is recorded that his eyes became bright (1 Sam 14:29). It follows, from the idea that a soundly functioning eye gave out light, that an eye that was struggling to make out detail was considered dim (Gen 27:1, 48:10; Job 17:7) and eyes that could not see were said to be darkened (Ps 69:23). Other examples are found at Deut. 28:65; Job 17:7; Ps 6:7, 38:10; Lam 5:17.

Amongst the Israelites in the days of Judah, Joshua or Jeremiah, the eye was an active agent, giving out rather than taking in, hence the Mishnah could refer to the outlet vent of an oven as its eye (m. Kelim 8:7 A). As the eye also gave out water (tears), the Hebrew word for eye (עַיִן = ayin) is also used of a spring (cf. Job 14:3 with Exod 15:27). The eye bestowed pity (Deut 7:16; Ezek 5:11) or favour (Deut 24:1; 1 Sam 20:3; Jer 24:6), cast a person down (Ps 17:11), mocked (Pr 30:17), winnowed evil (Pr 20:8), or administered support (2 Chr 16:9). As an active organ it could therefore grow weak (Ps 6:7). 

The Hebrew way of understanding the eye rather neatly explains some actions which might otherwise seem a little odd. For example, God does not hide offenders from his eyes, but hides his eyes from them, to graciously stop his eyes revealing their sin (Isa 1:15 ESV, cf. Job 14:3).

Because the eye was so intimately related to the function of judgement, the eyes of rebellious vassal leaders were often put out to ensure that they could never hold a place of authority again. For more on this practice see the notes on Matt 5:29-30.

References

Charles, Robert Henry. 2004. “The Book of the Secrets of Enoch.” Pages 425 to 469 in vol. 2 of Pseudepigrapha of the Old Testament. Ed. Robert Henry Charles. Bellingham, WA: Logos Research Systems.

Lichtheim, Miriam. 1973a. “Stela of Somtutefnakht.” Pages 41-3 in Volume 3 of Ancient Egyptian Literature. Berkeley: University of California Press.

Morenz, Siegfried and Anne E. Keep. 1992. Egyptian Religion. Cornell University Press.

Opperwall, Nola J. 2002. “Eye.” Page 249 in Vol. 2 of Geoffrey W. Bromiley Ed. The International Standard Bible Encyclopedia, Revised. Grand Rapids, Mich.: William B. Eerdmans, 1988; Wm. B. Eerdmans.