Beheld that which he did (qeasamenoi o epoihsen). First aorist middle participle of qeaomai and first aorist active indicative of poiew in the relative (o) clause. They were eye-witnesses of all the details and did not depend on hearsay. Believed on him (episteusan ei auton). Such a result had happened before ( Acts 7:31 ), and all the more in the presence of this tremendous miracle which held many to Jesus ( Acts 12:11Acts 12:17 ).