WHEN THE gods and the demons churned the milky ocean in days of yore, nectar came out of it. Lord Vishnu assumed the form of Mohini, a charming lady, deluded the demons and distributed the nectar only among the gods. But Rahu had disguised himself as a god. The sun and the moon pointed this out to Mohini who immediately slashed off the demon’s head. Since the nectar had by then already reached up to the neck, he did not die.
Thus the head came to be known as Rahu and the body as Ketu. To avenge this betrayal, Rahu and Ketu periodically eclipse the sun and the moon.
Astronomically speaking, when the sun, the moon and the earth are all in line, with the moon or the earth at the centre, a solar or lunar eclipse takes place respectively.
At the time of the eclipse, people bathe in the sacred rivers. They do charitable acts. They give cows, money and gold. The day after the eclipse they feed the poor, the Brahmins and the Sadhus. After the eclipse they clean their houses, vessels, etc., and take a bath before they start cooking.
One should not take food during the eclipse. When the eclipse begins the food should by then have been digested. One should take food only after seeing the sun or the moon free from the eclipse. When the clear sun or the moon is not seen before sunset or sunrise, in the case of the solar and lunar eclipse respectively, food can be taken only after the sun or the moon is seen the next day.
Pregnant women should not see the sun or the moon during the time of the eclipse. If they do the child born may have some kind of defect. He may be born deaf, dumb or blind. Householders are forbidden from sexual intercourse on the day of the eclipse, for the same reason.
At this time one should take great care in avoiding bleeding, scorpion stings, etc. These have disastrous results. Even an earthworm has a poisonous effect when it bites one during an eclipse.
Those who do Japa at the time of the eclipse derive great benefits. The effect of Japa and Sankirtan during the eclipse contributes towards relieving the suffering of humanity and also of the planets. These people receive the blessings of the gods. They attain perfection quickly. Those who wish to tap the subtle force locked in the Mantra that will cure scorpion stings should stand in water and repeat the appropriate Mantra.
The little intellect cannot understand many things in this universe. Hence, have faith in the words of sages.
Ignorance has eclipsed Self-knowledge. However, this eclipse will disappear. You will shine in your own glory. This is the spiritual significance of the eclipse.
(pgs 160-162, Hindu Fasts and Festivals)