Amataṃ tesaṃ viraddhaṃ, yesaṃ kāyagatā sati viraddhā.
Amataṃ tesaṃ aviraddhaṃ, yesaṃ kāyagatā sati aviraddhā.
Amataṃ tesaṃ aparibhuttaṃ, yesaṃ kāyagatā sati aparibhuttā.
Amataṃ tesaṃ paribhuttaṃ, yesaṃ kāyagatā sati paribhuttā.

“Those who have missed mindfulness of the body, have missed nibbāna. Those who have not missed mindfulness of the body, have not missed nibbāna. Those who have not made use of mindfulness of the body, have not made use of nibbāna. Those who have made use of mindfulness of the body, have made use of nibbāna.” (A.i.46)
(translator: possibly, U Sein Nyo Tun, because the same text is at http://www.aimwell.org/Books/Ledi/Anapanasati/anapanasati.html#BodyMindfulness)

Amata is an ambrosia of immortality. It also means a state of security from change. Amata is a synonym for nibbana. So, here we are talking about the realisation of the deathless, and the deathless realisation.

“Those who have made use of mindfulness of the body, have made use of nibbana.” The deathless is often made into something so aloof that the idea of ‘using’ the deathless is rarely heard of. It reminds me of Sariputta’s advice to Anaruddha to “turn toward the deathless.” Again, often we encouraged to be very passive in our relation with the immeasureable. So, these passages need investigating in our actual lives. How can we now make use of nibbāna? Maybe Buddhadasa’s idea (and I’m remembering this and not verifying the concept from his books, right now), the idea of little nibbānas that happen everyday, would be useful here?

Along with this teaching, or in the context of this teaching on the mindfulness of the body, there is a lovely teaching in the Majjhima Nikaya, the Samana-Mundika Sutta, where the Buddha says (in Bhikkhu Thanissaro’s translation):

“Now, an individual endowed with which ten qualities is one whom I describe as being consummate in what is skillful, foremost in what is skillful, an invincible contemplative attained to the highest attainments? One endowed with the right view of one beyond training, the right resolve of one beyond training, the right speech… the right action… the right livelihood… the right effort… the right mindfulness… the right concentration… the right knowledge… the right release of one beyond training. An individual endowed with these ten qualities is one whom I describe as being consummate in what is skillful, foremost in what is skillful, an invincible contemplative attained to the highest attainments.”

This is the ten-fold path = nibbāna = with the vision of things-as-they-are (which is right knowledge beyond training). The present path is the goal, the goal is the path. This very body – is the way and the goal.