The Time for Nirvana and Karma Changing
Maha Shivaratri means "The Great Night of Shiva". The night of Shiva falls on the eve of the New Moon. The night is symbolic of a condition prior to creation and refers to the chaos that existed before light. But this chaotic darkness is not a negative condition. It is pure consciousness without the pollution of knowledge. In the Buddha’s terminology, it is the Emptiness of Nirvana.
Every year during The Great Night of Shiva, Lord Shiva incarnates in the form of the Shiva Lingam. Maha Shivaratri is the prime time for every soul to get into the primordial consciousness of non-existence or Nirvana. One is required to keep vigil during the night in order to receive Shiva’s grace and assistance.
Source: AstroVed