अपाने जुह्वति प्राण प्राणेऽपानं तथाऽपरे।
प्राणापानगती रुद्ध्वा प्राणायामपरायणाः।।4.29।।
4.29 Constantly practising control of the vital forces by stopping the movements of the outgoing and the incoming breaths, some offer as a sacrifice the outgoing breath in the incoming breath; while still others, the incoming breath in the outgoing breath.
4.29 - 4.30 Other Karma Yogins are devoted to the practice of breath control. They are of three types because of the differences in inhalation, exhalation and stoppage of breath. Puraka (inhalation) is that in which the inward breath is sacrificed in the outward breath. Recaka (exhalation) is that when the outward breath is sacrificed in the inward breath. Kumbhaka (stoppage of breath) is that when the flow of both inward and outward breaths is stopped. The clause, restricting of diet, applies to all the three types of persons devoted to the control of breath. All these, according to their liking and capacity are engaged in performing the various kinds of Karma Yoga beginning from the sacrifice of material objects to the control of breath. They know and are devoted to sacrifices comprising obligatory and occasional rituals preceded by the performance of the great sacrifices (Panca-Maha-Yajna), as alluded to in Creating men along with the sacrifices (3.10). Because of this only, their sins are done away with. Those who are engaged in Karma Yoga by sustaining their bodies only by the ambrosia of sacrificial remains will go to the eternal Brahman. Go to Brahman here means realise the self which has Brahman for Its soul.
Apaane juhwati praanam praane’paanam tathaa’pare; Praanaapaana gatee ruddhwaa praanaayaamaparaayanaah.
apāne—the incoming breath; juhvati—offer; prāṇam—the outgoing breath; prāṇe—in the outgoing breath; apānam—incoming breath; tathā—also; apare—others; prāṇa—of the outgoing breath; apāna—and the incoming breath; gatī—movement; ruddhvā—blocking; prāṇa-āyāma—control of breath; parāyaṇāḥ—wholly devoted; apare—others; niyata—having controlled; āhārāḥ—food intake; prāṇān—life-breaths; prāṇeṣhu—life-energy; juhvati—sacrifice; sarve—all; api—also; ete—these; yajña-vidaḥ—knowers of sacrifices; yajña-kṣhapita—being cleansed by performances of sacrifices; kalmaṣhāḥ—of impurities