Avvaiyaar counsels King Adhiyamaan

She says "When the sight of an angry tiger, the deers flee, same way with the rising of an angry sun (shining bright) the darkness fades away"

Avvaiyar is a famous Tamil Poet/Saint

Image of Satguru Sivaya Subramuniyaswami
There is no way a mantra can be learned from a book and be effective. Therefore, approach the guru cautiously and with a full heart.