Lojong Meditation - Whatever You Meet Unexpectedly Join With Meditation...

When you run after your thoughts, you are like a dog chasing a stick: every time a stick is thrown, you run after it. Instead, be like a lion who, rather than chasing after the stick, turns to face the thrower. One only throws a stick at a lion once.

Milarepa 

“Just as it is known that an image of one's face is seen depending on a mirror but does not really exist as a face, so the conception of "I" exist dependent on mind and body, but like the image of a face the "I" does not at all exist as its own reality."   Nagarjuna

"Thanks to impermanence, everything is possible.  Nagarjuna

Link to The Slogans of Atisha. Thirty nine slogans used in Lojong Mind Training.