HH Jigme Phuntsok Rinpoche
When I was a student in Sershul, my teacher, Thubga Rinpoche, once said, "If we don't try to tame our mind, the mind will overpower us with its fearsome power. But if we do try to tame the mind, we will discover that it’s nothing more than a paper tiger (easily subdued). Even if we dedicate only seven days to sincerely praying to our Guru and seriously train our mind, our mental state will be vastly different from before."
I had unshakable faith in my teacher's words. In reality, taming the mind isn't so difficult with the sublime pith instructions if you only put in the effort. The only reason we haven't succeeded yet is that we have not truly dedicated ourselves to the task.