The Correct Method of Breathing Buddha Recitation

When recollecting the Buddha (buddhānusmṛti), if a sound flows out beyond the chest cavity and the mouth, it means the breath is moving from the dantian to inside and outside the body and beyond it — this is a process of releasing the breath. In that case, one cannot recite while inhaling, because the inhaled breath would collide with the sound stream of the recitation, making recitation impossible. One can only recite while exhaling; when inhaling, one must inhale single-mindedly, placing all attention on the process of inhalation. Wherever the breath goes, the attention must follow, so that the vital energy and blood flow smoothly, body and mind feel comfortable, and the mind settles into concentration very quickly. 

When inhaling, the breath enters through the nostrils and goes all the way down to the dantian. If one's mental power is sufficient, one can let it reach the four limbs and every pore of the whole body, while at the same time attentively observing and feeling the bodily sensations. When exhaling again, the breath exhaled is slight and gentle, because all the cells of the body carry out metabolism and expel waste gases; these waste gases are expelled through the pores of the whole body — the pores can also breathe. 

The method of reciting the Buddha's name in coordination with the breath can unify mind and breath, harmonize body and mind, make the vital energy and blood flow smoothly, lead to swift attainment of meditative concentration (samādhi), deep concentration, and long duration of meditative absorption. Beginners in cultivating concentration should start from this method. For the specific method of reciting the Buddha's name, see the book Cultivating Samādhi and Investigating Chan to Realize the Path.