大方便佛報恩經 1.26

1.26

爾時彼佛告諸菩薩言：「善男子！汝往娑婆世界，若見彼佛，應生供養、恭敬、難遭之想。何以故？釋迦如來於無量百千萬億阿僧祇劫，難行苦行，發大悲願：『若我得成佛時，當於穢惡國土，山陵、堆阜、瓦礫、荊棘，其中眾生具足煩惱，五逆十惡，於中成佛而利益之，使斷一切苦，獲一切樂，成就法身，永盡無餘。』其佛本願如是。汝等今往，當如佛往，住如佛住。」

Then that buddha said to the bodhisattvas: "Good sons! When you go to the Sahā world and see that buddha, you should give rise to thoughts of making offerings, showing reverence, and [recognizing how] difficult it is to encounter [him]. Why is this? Śākyamuni Tathāgata, throughout immeasurable hundreds of thousands of ten-millions of kotis of asaṃkhyeya kalpas, underwent difficult practices and austerities, and made a great compassionate vow: 'When I attain Buddhahood, it should be in a defiled and evil land, with mountains and mounds, rubble and thorns, wherein sentient beings are fully beset by afflictions and the five deadly sins and ten unwholesome deeds; amidst them I shall attain Buddhahood to benefit them, causing them to sever all suffering, obtain all bliss, accomplish the dharmakāya, and end [samsara] forever without remainder.' Such was that buddha's original vow. Now as you go, you should go as a buddha goes, and dwell as a buddha dwells."