1Thus have I heard. On one occasion the Blessed One was dwelling at Vesālī in Ambapali's Grove. There the Blessed One addressed the bhikkhus thus: "Bhikkhus!" [n.122] What follows is the uddesa (condensed statement) of the Satipaṭṭhāna Sutta (DN No. 22; MN No. 10) without the niddesa (elaboration). Full-length commentaries on the text are at Sv III 741–61 and Ps II 244–66; the commentary in Spk is much abridged. The relevant passages, with excerpts from the subcommentary, are translated in Soma, The Way of Mindfulness, pp. 35–64. The commentaries offer two derivations of satipaṭṭhāna: one from sati + upaṭṭhana, "the establishment of mindfulness"; the other from sati + paṭṭhana, "the foundation of mindfulness." The former emphasizes the act of setting up mindfulness, the latter the objects to which mindfulness is applied. While the commentaries lean towards the derivation from sati + paṭṭhana, the former is certainly more original and is supported by the Skt smṛtyupasthana. See too the common expressions, upaṭṭhitasati, "with mindfulness established" (e.g., at SN54.13; V 331,10, etc.) and parimukhaṁ satiṁ upaṭṭhapetva, "having established mindfulness in front of him" (e.g., at SN54.1; V 311,13, etc.). Paṭis, by consistently glossing sati with upaṭṭhana, also shows a preference for this derivation. For a brief explanation of the expression according to the commentarial method, see Vism 678–79 (Ppn 22:34).

"Venerable sir!" the bhikkhus replied. The Blessed One said this:

2"Bhikkhus, this is the one-way path for the purification of beings, for the overcoming of sorrow and lamentation, for the passing away of pain and displeasure, for the achievement of the method, for the realization of Nibbāna, that is, the four establishments of mindfulness. [n.123] Ekāyano ayaṁ maggo is often translated "This is the only way" (Soma) or "This is the sole way" (Nyanaponika), implying that the Buddha’s way of mindfulness is an exclusive path. The commentary to the Satipaṭṭhāna Sutta, however, gives five explanations of the phrase, of which only one suggests exclusivity (see Sv III 743–44; Ps I 229–30; translated in Soma, The Way of Mindfulness, pp. 36–39). Spk here mentions only the first: ekamaggo ayaṁ bhikkhave maggo, na dvedhāpathabhūto; "a single path, bhikkhus, is this path, not a forked path." Ekāyana magga occurs elsewhere in the Nikāyas only at MN I 74,14–15 foll., where it clearly means a path leading straight to its destination. I thus understand the metaphorical use of the phrase to be a way of indicating that satipaṭṭhāna leads straight to "the purification of beings," etc.; perhaps the way of mindfulness is being contrasted with other types of meditation that do not always lead straight to the goal. For a fuller discussion, see Gethin, The Buddhist Path to Awakening, pp. 59–66. The word should not be confused with ekayāna, "one vehicle," the central theme of the Saddharma Puṇḍarika Sūtra.
Spk explains the "method" (ñaya) as the Noble Eightfold Path. Thus, by developing the path of satipaṭṭhāna, which is mundane in the preliminary phase, one eventually achieves the supramundane path. On ñaya, see II, n. 122. What four?

"Here, bhikkhus, a bhikkhu dwells contemplating the body in the body, ardent, clearly comprehending, mindful, having removed covetousness and displeasure in regard to the world. [n.124] For a translation of the commentarial passage on this basic formula, see Soma, The Way of Mindfulness, pp. 51–64. An early word gloss is at Vibh 194–95. Gethin discusses the basic formula, Buddhist Path to Awakening, pp. 47–53.
A few key points: The repetitive phrase "contemplating the body in the body" (kāye kāyānupassi) serves "to determine the object (the body) by isolating it" from other things such as feeling, mind, etc., and to show that one contemplates only the body as such, not as permanent, pleasurable, a self, or beautiful. Similarly in regard to the other three establishments. "Ardent" (ātāpi) connotes energy, "clearly comprehending" (sampajāno) implies wisdom. "Covetousness and displeasure" (abhijjhā-domanassa) are code words for the first two hindrances, and thus their removal may be understood to imply some success in concentration. Thus altogether four of the five spiritual faculties (indriya) are indicated here, and while faith is not mentioned it is clearly a prerequisite for taking up the practice in the first place.
Spk glosses vineyya: tadaṅgavinayena vā vikkhambhanavinayena vā vinayitvā, "having removed: having removed by removal in a particular respect or by removal through suppression." "Removal in a particular respect" signifies temporary removal by deliberate restraint or by insight, "removal through suppression" temporary removal by the attainment of jhāna. The phrase need not be understood to mean that one must first abandon the hindrances before one starts to develop the four establishments of mindfulness. It would be sufficient to have temporarily suspended "covetousness and displeasure" through dedication to the practice itself. He dwells contemplating feelings in feelings, ardent, clearly comprehending, mindful, having removed covetousness and displeasure in regard to the world. He dwells contemplating mind in mind, ardent, clearly comprehending, mindful, having removed covetousness and displeasure in regard to the world. He dwells contemplating phenomena in phenomena, ardent, clearly comprehending, mindful, having removed covetousness and displeasure in regard to the world.

"This, bhikkhus, is the one-way path for the purification of beings, for the overcoming of sorrow and lamentation, for the passing away of pain and displeasure, for the achievement of the method, for the realization of Nibbāna, that is, the four establishments of mindfulness."

3This is what the Blessed One said. Elated, those bhikkhus delighted in the Blessed One's statement. sn.v.142

1Evaṁ me sutaṁ—​ ekaṁ samayaṁ bhagavā vesāliyaṁ vihārati ambapālivane. Tatra kho bhagavā bhikkhū āmantesi: "bhikkhavo"ti.

"Bhadante"ti te bhikkhū bhagavato paccassosuṁ. Bhagavā etadavoca:

2"Ekāyanvāyaṁ, bhikkhave, maggo sattānaṁ visuddhiyā sokaparidevānaṁ samatikkamāya dukkhadomanassānaṁ atthaṅgamāya ñāyassa adhigamāya nibbānassa sacchikiriyāya, yadidaṁ – cattāro satipaṭṭhānā. Katame cattāro?

Idha, bhikkhave, bhikkhu kāye kāyānupassī vihārati ātāpī sampajāno satimā, vineyya loke abhijjhādomanassaṁ; vedanāsu vedanānupassī vihārati ātāpī sampajāno satimā, vineyya loke abhijjhādomanassaṁ; citte cittānupassī vihārati ātāpī sampajāno satimā, vineyya loke abhijjhādomanassaṁ; dhammesu dhammānupassī vihārati ātāpī sampajāno satimā, vineyya loke abhijjhādomanassaṁ.

Ekāyanvāyaṁ, bhikkhave, maggo sattānaṁ visuddhiyā sokaparidevānaṁ samatikkamāya dukkhadomanassānaṁ atthaṅgamāya ñāyassa adhigamāya nibbānassa sacchikiriyāya, yadidaṁ – cattāro satipaṭṭhānā"ti.

3Idamavoca bhagavā. Attamanā te bhikkhū bhagavato bhāsitaṁ abhinandunti.

Paṭhamaṁ.