Guess the 6 letter Title in the comment

I am the most powerful, 

but you don't understand mournful!

The more long, slow and deep I am,

the better shall be the quality of your life span.

The more hasty, fast and anxious I am,

the worse shall be your life exam.

You try to stop me for a few minutes?

Your body shall be out of the vital spirit.

Remember, the entire life resides in my being, 

Sit back, reflect and start seeing. 

At first it will be difficult. 

To understand that my nature is mystical.

Try to concentrate on me in moments critical, 

And your life shall turn into a miracle!

 But once you attempt in life to master this art,

The world shall be in your heart!

Ah, you know who I am?

I am the be-with all of your life Goddamn!