Albert Barnes Commentary Esther 8:3

"And Esther spake yet again before the king, and fell down at his feet, and besought him with tears to put away the mischief of Haman the Agagite, and his device that he had devised against the Jews." — Esther 8:3 (ASV)

Though Haman was dead, his work was not yet undone. The royal decree had gone out, and, according to Persian notions, could not be directly recalled or reversed (Esther 8:8). Mordecai did not dare, without express permission from the king, to take any steps, even to stay the execution. And Esther, being in favor, once more took the initiative.