Ganesha, the remover of obstacles, governs muladhara, our root/base chakra. With his elephant head, human body, and portly belly, Ganesha is one of the most recognized deities of the Hindu pantheon. His job is to clear obstacles, grant new perspectives, and guide us to recognize our strength and wisdom.
Ganesha blesses all beginnings and as the deity of the first chakra, he asks us to connect to our bodies and to the earth. For many people, there is disconnect from our bodies. We move through daily routine without conscious attention to our actions. We swallow a pill to numb pain, eat quickly or distractedly, spend more time in our head than our body; when we do pay attention to our body, we berate it.
Ganesha, commonly depicted with four arms, holds a goad in one hand to prod humans forward on the path to enlightenment. Muladhara chakra establishes survival, stability, and security. Without a strong connection to your body or to the earth element, how can you expect to listen to your breath or manifest intention? When you align your body and emotions, you manifest your ability to live a full life.
Perhaps you have seen images depicted of Ganesha with an elephant head and a fat human body as riding a mouse/rat. If not, view the image above.
Rats/Mice and humans have a lot in common. We both dig the earth to make a home for ourselves. We both have and display greed when it comes to collecting material wealth or food. We both remain completely oblivious to the fact that one day we need to die, and instead we try and breed and prolong our age and name/fame. And other similarities.
Elephants have a peculiar nature, which is very useful to humans. Think of a dark and dense/thick forest full of shrubs, thickets, thorns and trees and you need to cross it to reach the other side. You do not know where to step and which way to go or which path to take. So, you wait, until an elephant goes through that forest, it's natural home. When an elephant goes through a thick forest, it will stamp down shrubs and small plants down to earth, will crush and tear apart tree branches away from it's way. Thus, the elephant will clearly lay a path to walk on in it's wake when it walks through that thick forest. And a human can use that path created by the elephant to successfully cross that thick forest and reach the other side.
Now, in above para, replace the other side of the forest with a goal you need to achieve in your life, and replace the thick forest with hurdles and difficulties that you will encounter in your path......now you understand why you pray to Ganesha and ask him to remove hurdles in your way to achieve your particular task.
A human sees that same Ganesha riding a rat/mouse. That means nothing more than a human seeking that Ganesha to ride our human lives so that we develop strength and resilience in countering hurdles that come our way and reach our destination/goals successfully. This is the secret behind why Ganesha, an elephant headed fat human bodied god is depicted as riding a rat/mouse.