佛說佛名經 17.42

17.42

「復次，比丘！復有第三人，取彼爾所世界微塵，過彼爾所微塵數世界為一步，過彼若干百千萬億那由他阿僧祇劫，行乃下一塵，如是盡諸微塵。復有第四人，取彼若干微塵數世界，若著微塵若不著微塵，下至水際上至有頂滿中微塵。比丘！於意云何？彼諸微塵可知數不？」

"Furthermore, bhikṣu, suppose a third person were to take the fine dust motes of that many worlds, pass that many worlds as there are fine dust motes in a single step, and traveling through that many hundreds of thousands of myriads of koṭis of nayutas of asaṃkhyeya kalpas, would only then deposit a single dust mote, exhausting all the fine dust motes in this manner. Suppose a fourth person were to take that number of worlds as there are fine dust motes, whether having had a dust mote placed in them or not, and fill them completely with fine dust motes down to the water limit and up to Bhavāgra. Bhikṣu, what do you think? Could the number of those fine dust motes be known?"