Ganesh Chaturthi is the birthday of Lord Ganapati and is celebrated every year on the 4th day of the waxing fortnight, during the month of the Bhadrapada (the 6th month as per the Indian calendar).
Let us understand the significance hidden within this day.
Sixth month- The number 6 symbolizes that the energy, which we are worshipping as Ganapati, is over and above the 5 basic elements of earth, water, fire air and space.
Waxing fortnight- This signifies knowledge (jnana). We are seeking that knowledge.
The 4th day (Chaturthi)- The number 4 symbolizes that this God is over and above the 3 attributes i.e. the traits of goodness, passion and ignorance (Sattva, rajas and tamas) and also over and above the 3 states of existence (waking, dream and deep sleep states). This is the absolute supreme state!
Therefore, in a nutshell, it can be said that the Supreme Lord who is over and above the 5 basic elements, the 3 states of existence as well as the 3 traits is worshipped on this day in the name of Ganapati.
Bhaktimala