iti bruvanam nrpatim
maitreyah uvaca—the great sage Maitreya continued to speak; iti—thus; bruvanam—while speaking; nr-patim—the King; pitr—the denizens of Pitrloka; deva—the demigods; dvi-jatayah—and the twice-born (the brahmanas and the Vaisnavas); tustuvuh—satisfied; hrsta-manasah—greatly pacified in mind; sadhu-vadena—by expressing congratulations; sadhavah—all the saintly persons present.
The great sage Maitreya said: After hearing King Prthu speak so nicely, all the demigods, the denizens of Pitrloka, the brahmanas and the saintly persons present at the meeting congratulated him by expressing their good will.
When a person speaks very nicely at a meeting, he is congratulated by the audience, who express their good will with the words sadhu, sadhu. This is called sadhu-vada. All the saintly persons, Pitas (denizens of Pitrloka) and demigods who were present at the meeting and heard Prthu Maharaja expressed their good will with the words sadhu, sadhu. They all accepted the good mission of Prthu Maharaja, and they were fully satisfied.
Link to this page: https://prabhupadabooks.com/sb/4/21/45