The name of the mace, or gada, of Hindu God Vishnu is known as Kaumodaki. It symbolically represents the power in the Lord with which He knocks down the men who run after sense gratifications and are overpowered by ego. It is a symbol of ‘Danda’ or punishment. The mild knocks from the mace in the form of disappointments, dissatisfactions and loss takes a man to the correct path – the path that leads to the Supreme Truth.
The mace is also said to represent the occasional knocks that the mind generates – the knocks that pressures us to think who we are, the source, is there bliss etc. These questions put one in a spiritual path.
Another symbolism suggests that the mace represents the strength – the strength required to satisfy hunger.
Alan Danielou writes:
The power of knoweldge dazzles and intoxicates the mind hence the mace is called the stupefire of the mind - Kaumodaki. The power of knowledge is the essence of life from which all physical and mental powers are derived. Nothing else can conquer time and itself become power of time. As such the mace is identified with Goddess Kali, who is the power of time. The mace is Kali, power of time. It destroys all that opposes it. (Hindu Polytheism, p. 157)