Sight seems to play an awfully large role in our parsha:
1) The parsha opens with Avraham seeing guests arriving -- this one counts as a double: "Vayar... Vayar vayaratz likrasam."
2) "Erdah na v'ereh" -- Hashem goes down and see what is going on in Sdom.
3) The people of Sdom are struck blind, they lose their ability to see, when they attempt to break into Lot's house.
4) Lot's wife looks back to see the destruction of Sdom and gets turned into a pillar of salt.
5) Avimelech's gift to Sarah is described as a "ksus eynaim," a covering for her eyes.
6) Hagar does not see the well she needs to get water for Yishmael till a Malach points it out to her (21:19) She names the place "Be'er Lachai Ro'i."
7) "Vayar es hamakom mei'rachok," we are told that Avraham sees Har HaMoriah, the spot of the akeidah, from a distance.
8) Avraham sees a ram which he had not noticed before and uses it as a korban in place of his son.
9) Avraham names the place "Hashem Yireh," the place where Hashem is seen.
Anything I miss? What is especially interesting is the multiple examples of people not seeing things that are there in front of them. The gemara says that Avraham sent Eliezer out to look for orchim, but Eliezer didn't see any; Avraham then went out himself and saw the three guests. The well Hagar found was there all along, yet until the malach pointed it out she was unaware of it. The ram which took Yitzchak's place must have been there, yet it seems from the language of "vayisa es einav," that Avraham at first did not notice it. The Sefas Emes and others play up this theme and write that everything we need in life is here for us, all the opportunities, all the kochos to take advantage of them, but we walk around blind to what is in front of our eyes. Commenting on the question of how the sons-in-law of Lot could mock the angels' threat of destroying Sdom when they had already seen the power of the angels to strike blind the unruly mob who came to assault Lot, the Shem m'Shmuel writes that there is a blindness of the soul as well as physical blindness. The sons-in-law of Lot could physically see, but like the other inhabitants of Sdom, they could not process the fact that there is a din v'dayan in the world; they lacked inner vision. (Adam and Chavahs eye-opening experience of eating from the eitz ha'da'as ["Vatipakachna einei she'neihem"] midah k'negged midah blinded their spiritual eyes.) I'm not sure else to make of all these examples or even whether there is anything else to make of it -- something to think about.