1At Sāvatthī. "Bhikkhus, there are these Four Noble Truths.
"What four?
The noble truth of suffering,
the noble truth of the origin of suffering,
the noble truth of the cessation of suffering,
the noble truth of the way leading to the cessation of suffering.

It is because he has fully awakened to these Four Noble Truths as they really are that the Tathāgata is called the Arahant, the Perfectly Enlightened One.

2"Therefore, bhikkhus, an exertion should be made to understand: ‘This is suffering.’[n.376] Tasmātiha bhikkhave idaṁ dukkhan ti yogo karaṇīyo. Spk: Since a concentrated bhikkhu understands the Four Noble Truths as they really are, therefore you should make an exertion to become concentrated in order to understand the four truths as they really are. And since the round of existence increases for those who do not penetrate them, but stops increasing from the time they are penetrated, therefore you should make an exertion to understand them, thinking, "Let the round not increase for us."
An exertion should be made to understand: ‘This is the origin of suffering.’
An exertion should be made to understand: ‘This is the cessation of suffering.’
An exertion should be made to understand: ‘This is the way leading to the cessation of suffering.’"

1Sāvatthinidānaṁ. Cattārimāni, bhikkhave, ariyasaccāni. Katamāni cattāri? Dukkhaṁ ariyasaccaṁ … pe … dukkhanirodhagāminī paṭipadā ariyasaccaṁ – imāni kho, bhikkhave, cattāri ariyasaccāni.

Imesaṁ kho, bhikkhave, catunnaṁ ariyasaccānaṁ yathābhūtaṁ abhisambuddhattā tathāgato ‘arahaṁ sammāsambuddho’ti vuccati.

2Tasmātiha, bhikkhave, ‘idaṁ dukkhan’ti yogo karaṇīyo … pe … ‘Ayaṁ dukkhanirodhagāminī paṭipadā’ti yogo karaṇīyo"ti.

Tatiyaṁ.