अथ यदवोच भू प्रपद्य इति पृथिवींप्रपद्येऽन्तरिक्ष प्रपद्ये दिव प्रपद्य इत्येवतदवोचम् ॥ ५ ॥
In plain words
Now, when he declared 'I take refuge in the earth-realm,' he meant precisely this: 'I take refuge in the earth, I take refuge in the atmosphere, I take refuge in heaven.'
Close to the Sanskrit
Now, that which he spoke, 'I take refuge in bhu' — thus indeed I spoke: 'I take refuge in the earth, I take refuge in the atmosphere, I take refuge in heaven'.