त्रयाः प्राजापत्याः प्रजापतौ पितरिब्रह्मचर्यमूषुर्देवा मनुष्या असुरा उषित्वाब्रह्मचर्यं देवा ऊचुर्ब्रवीतु नो भवानितितेभ्यो हैतदक्षरमुवाच द इति व्यज्ञासि-ष्टा३ इति व्यज्ञासिष्मेति होचुर्दम्यते-ति न आत्थेत्योमिति होवाच व्यज्ञासि-ष्टेति ॥
In plain words
Three kinds of children lived with Prajāpati their father as students: gods, men, and demons. When their time of discipleship was over, the gods spoke up first: 'Won't you teach us, sir?' To them he answered with a single syllable -- 'da' -- and asked, 'Have you understood?' 'We have,' they said. 'It means: restrain yourselves.' 'Isn't that just what you said?' 'Yes,' he replied, 'you have understood.'
Close to the Sanskrit
Three kinds of Prajāpati's offspring -- gods, men, and demons -- dwelled with Prajāpati their father in studentship. Having dwelled in studentship, the gods said: 'Let sir speak to us' -- thus. To them he uttered this one syllable: 'da' -- thus. 'Have you understood?' -- thus. 'We have understood' -- thus they said -- '[it means] restrain yourselves' -- thus -- 'is that not what you have said?' -- thus. 'Om (yes)' -- thus he said -- 'you have understood' -- thus.