Jewish Sexuality dot Com

The account of Eve's tragic error is found in the very first portion of the Torah, “Bereishit,” as it says:
“And the woman SAW that the tree was good for eating, and that is was a DESIRE TO THE EYES….”   Just like with the Internet.
Too bad that Eve didn’t have a filter on her computer. The rest is history.
After Eve convinced Adam to eat the forbidden fruit with her, the Torah relates:
“Then the eyes of both of them were opened and they realized they were naked.”
The Torah commentator, the Sforno, explains that previous to their sin, the sexual act was performed to fulfill the Divine commandment to be fruitful and multiply. But now they felt shame in their sexuality and nakedness in that the primary function of their sexuality became the selfish satisfaction of sensual desire. They now displayed a desire for every base pleasure, despite its harmfulness.
Rabbi Shimson Raphael Hirsh writes that man need not be ashamed of his sexuality, as long as it stands in the service of the Almighty, as set down in the laws of marital relations. But when this condition is lacking, man feels ashamed in his nakedness, awakening the Divine voice within us, reminding us that we are not meant to be beasts.
Preceding their transgression was another example of the dangers of following after one’s eyes, in the wickedness of the serpent, the world’s very first pornographer. The Torah states that “the serpent was cunning beyond any beast of the field.” Rashi explains  that the lust and jealousy of the serpent was aroused when he SAW Adam and Eve engaging in marital relations, unashamed and unconcealed, “in the eyes of all” (Bereishit, 3:1, Rashi).
The jealous lust of the serpent led to the downfall of mankind. Adam and Eve were subsequently expelled from the Garden, and man has been trying to return ever since.    
Adam and Eve should have waited patiently until nightfall when  darkness would have provided the cover and modesty that marital relations require. The “Tikunei Zohar” explains that by waiting until nightfall, Shabbat would have arrived, with the special blessing it provides. With the added holiness of Shabbat, their union would have been the crescendo of all Creation, bringing Redemption to the world. The Arizal explains that a Torah scholar should reserve his time of marital relations to after midnight on Shabbat, precisely because of the special blessing of absolute Hesed (Divine Loving-kindness) that comes to the world at that time (“Taamai HaMitzvot,” Bereishit, 6-8). Children who are conceived at this hour begin their lives with a unique holy blessing that paves their way to a life filled with Torah. In contrast, before midnight, especially during weekdays, there are destructive spiritual forces and harsh judgments which hold sway in the world which influence marital relations in a negative manner. Children conceived at this time will find it more difficult to form a bond to the Torah (Zohar, Amor). After midnight on weekdays, there is a lessening of the harsh judgments, and this is the additional time that ordinary people should engage in marital relations (see the Laws of Marital Relations for a more detailed examination of this topic).
The Arizal continues his discussion of the mitzvah of procreation (loc cited) by emphasizing the mistake of conducting marital relations by the light of a candle (daylight, moonlight, or other light source). He stresses that children born from such unions will be handicapped in some manner (See, Pesachim 112B).  We can understand this as meaning the blemish can be spiritual or physical, G-d forbid, or, for instance, express itself in learning difficulties, hyperactivity, delinquency, and the like, such as with Cain.  Even if the wife is already pregnant, relations conducted in the light can negatively influence the fetus and eventual baby.
Thus we learn that the life of a child depends on its very beginning.  The Torah portion of Bereishit teaches us that it is up to parents to conduct their marital relations in a holy and modest fashion, in order to draw down a holy blessing on their offspring that will accompany them during their lifetime.