Mahaaraahulovaadasutta, Co no 5
Sutta passage:
Addasaa kho aayasmaa saariputto aayasmanta.m Raahula.m a~n~natarasmi.m
rukkhamuule nisinna.m palla'nka.m aabhujitvaa uju.m kaaya.m
pa.nidhaaya parimukha.m sati.m upa.t.thapetvaa. Disvaana aayasmanta.m
Raahula.m aamantesi : aanaapaanasati.m Raahula bhaavana.m bhaavehi,
aanaapaanasati Raahula bhaavitaa bahuliikataa mahapphalaa hoti
mahaanisa.msaa ti.

The venerable Sariputta saw the venerable Rahula seated at the foot of that
tree, cross-
legged and body upright with mindfulness established before him.
Having seen the venerable Rahula, he addressed him: "Cultivate the
development of mindfulness on in and out breathing, Rahula. The
development of mindfulness on in and out breathing, Rahula, is of
great fruit and profit."

Commentary: We read < Although the Blessed One saw that Rahula had returned
he did not say to him:" Do not return, because it is the time for you to
receive almsfood (bhikkaacaarakaalo)." Why? It is explained thus: It
occurred to the Buddha :" Today Rahula will eat the food of Deathlessness
(amatabhojana.m), namely, Mindfulness of the Body (kaayagataasati).
It is said, Addasaa kho aayasmaa saariputto, when the Blessed One had gone,
Sariputta who came afterwards saw him. >
We read that Sariputta after the Buddha had gone on his almsround, left his
dwellingplace, that he swept the place and threw away rubbish where
necessary, and set out pots with drinking water. He went to the sick and
asked, "Friend, what shall I bring you, what do you need?" He went to the
young monks who were newly ordained and exhorted them, saying, "Rejoice,
friend, be not discontented. The Teachings contain a practice that is most
excellent in substance (abhiramatha aavuso maa ukka.n.thittha
pa.tipattisaaraka.m Buddhasaasananti)." After he had acted thus, he went on
almsround after all the (other) bhikkhus had gone. The text states:
<When he went out on that day he saw "Lucky Rahula" (Raahulabhadda.m),
a~n~natarasmi.m
rukkhamuule nisinna.m, seated at the foot of a certain tree; he saw him, as
was said, when he came afterwards.
Then, why did he exhort him to develop Mindfulness of Breathing? Because it
is suitable for sitting. It is said that the Thera had not observed that the
Buddha had spoken about the meditation subject of matter
(ruupakamma.t.thaana.m) to Rahula. He thought that for him who was seated in
that way, glued on his seat and immovable, this subject of meditation in a
sitting posture was suitable, and thus he spoke to him in that way.
As regards the word, aanaapaanasati, mindfulness of breathing, he explained:
"After you have grasped inbreathing and outbreathing, and attained the
fourth or the fifth stage of jhana, and you have developed vipassana,
insight, reach arahatship."
*****
Nina.