षोडशकलः सोम्य पुरुषः पञ्चदशाहा- नि माशीः काममपः पिबापोमयः प्राणो नपिबतो विच्छेत्स्यत इति ॥ १ ॥
In plain words
Gentle one, the human person is composed of sixteen parts. Do not eat any food for fifteen days, but drink water as much as you like. Since breath is sustained by water, your life-force will not be severed as long as you drink water.
Close to the Sanskrit
Sixteen-parted, O gentle one, is the person. For fifteen days do not eat; as you desire, drink water. Water-consisting is the breath; of one who drinks [water], [the breath] will not be cut off, thus.