Mercury can be a powerful tool for success. Mercury is a planet of mental energy. It is our intelligence and how we communicate. When we use Mercury in a constructive way, we can discriminate between truth and falsehood, and learn quickly with mental flexibility.
If Mercury energy become unstable you started to be destructive, though, making us easily influenced by other’s opinions rather than truth, and willing to manipulate others to get what we want. 

Budha mantras: 
“Om budhaya namaha” 
“Om bram brim braoum saha budhaya namaha”