kramato gam padaikena
dvitiyena divam vibhoh
kham ca kayena mahata
tartiyasya kuto gatih
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Vamanadeva will first occupy the three worlds with one step, then He will take His second step and occupy everything in outer space, and then He will expand His universal body to occupy everything. Where will you offer Him the third step?
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Sukracarya wanted to tell Bali Maharaja how he would be cheated by Lord Vamana. “You have promised three steps,” he said. “But with only two steps, all your possessions will be finished. How then will you give Him a place for His third step?” Sukracarya did not know how the Lord protects His devotee. The devotee must risk everything in his possession for the service of the Lord, but he is always protected and never defeated. By materialistic calculations, Sukracarya thought that Bali Maharaja would under no circumstances be able to keep his promise to the brahmacari, Lord Vamanadeva.