There are a number of legends centered on the reasons for Shri Ganesha’s one broken tusk.
One of the most popular legends is that Lord Ganesha broke one of the tusks to write the epic Mahabharata. It is said that Maharshi Vyasa had asked Ganesha to write the Mahabharata while he dictated it. Lord Ganesha readily agreed, but said that His pen would not stop writing until the entire epic was completed. Maharshi Vyasa agreed, but also put his own condition, that Lord Ganesha should write only after he has properly understood what was being dictated. Hence, Maharshi Vyasa took quite a long time to narrate the verses as Lord Ganesha would stop him from time to time to understand the more complicated verses. Together, they thus compiled the words of wisdom that are enshrined in the epic Mahabharata.
The tusk on the left side of the trunk is broken |
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Another Hindu mythological legend narrates this story of the reason for Lord Ganesha’s broken tusk: Lord Ganesha attended a feast specially arranged for his birthday by Lord Indra. At the feast, he ate lots of modaks. Subsequently, Lord Ganesha lost his balance from His mount, the mouse. All the modaks Lord Ganesha had eaten fell out of His belly. Seeing this, the other Gods smiled but did not laugh loudly, unlike the Moon God who not only laughed loudly and for long, but also mercilessly teased Lord Ganesha, making fun of His huge belly. In anger, Lord Ganesha broke off one of His tusks and flung it at the moon and gave a curse: He told the Moon that since the Moon was always arrogant about his beautiful face, that face would blacken and forever be hidden from everybody. Immediately, dark spots started appearing on the Moon's face. The other Gods pleaded with Lord Ganesha not to give such a terrible curse, as otherwise the world would only have the burning heat of Lord Surya, the Sun, and no cooling effects which are created by the Moon God. The Moon, too, apologized to Lord Ganesha, who then changed the curse slightly and declared that for 15 days, the Moon would shine brightly and for 15 days the face would darken - thus we see the waxing and waning of the Moon. Due to the curse given by Lord Ganesha, it is believed that whosoever looked at the moon on Lord Ganesha's birthday (Ganesh Chaturthi) could possibly be accused of being a thief. Today, it is believed that the dark dent on the moon was caused by Lord Ganesha’s throwing of the tusk piece at the moon; and on Ganesh Chaturthi devotees avoid looking at the moon.
As for the modaks which fell out of Lord Ganesha's belly, Lord Ganesha put all the modaks back in His belly and tied it up with a snake. Some Ganpati idols are thus depicted with the snake around the belly.
Read here for more details and photo of Ganpati idol with snake: Lord Ganesha Symbolism
{Note: Some legends state Lord Ganesha did not break His tusk to throw at the Moon God, but only gave the curse}
As for the modaks which fell out of Lord Ganesha's belly, Lord Ganesha put all the modaks back in His belly and tied it up with a snake. Some Ganpati idols are thus depicted with the snake around the belly.
Lord Siddhivinayak with snake around belly |
{Note: Some legends state Lord Ganesha did not break His tusk to throw at the Moon God, but only gave the curse}
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Yet another legend has it that the broken tusk is due to Lord Ganesha’s respect for His father, Lord Shiva. As the legend goes, the sage Parashurama once visited Lord Shiva’s abode. However, as Lord Shiva was asleep, Lord Gansha did not allow Parashurama to enter. Parashurama was adamant on entering, but Lord Ganesha was equally determined that His father should not be disturbed. A battle began between Lord Ganesha and Parashurama, during which the enraged sage threw his axe forcibly at Lord Ganesha. Although Lord Ganesha could have warded it off with His own power, He did not do so as the axe is one of Lord Shiva’s weapons. Hence out of respect to His father, Lord Ganesha did not stop the axe from hitting Him. Instead, he bowed in reverence to the weapon, and one of His tusks took the impact of the axe, thereby breaking it.