Sforno on Genesis 24:21/ספורנו על בראשית כ״ד:כ״א

1Wondering at her. He was amazed at her zeal.

2Remained silent. He did not try to dissuade her from troubling herself. Waiting to determine. The way she performed her good deeds was to be the test.

3Whether Ad-noy had made. If she acted out of pure kindness he would know that his mission was successful.

4Or not. If she expected payment she was not the right one