Exegesis:

ouk ischusan epilabesthai autou rēmatos ‘they could not catch him in (one) word,’ cf. on v. 20. For ischuō cf. on 6.48.

enantion tou laou ‘in the presence of the people,’ i.e. ‘with the people present,’ or ‘in public.’

thaumasantes epi tē apokrisei autou ‘astonished at his answer,’ here with negative connotation, ‘taken aback.’ apokrisis, cf. on 2.47.

esigēsan ‘they fell silent,’ ingressive aorist.

Translation:

In the presence of the people, cf. also on 8.47.

Marvelling at, cf. on “wondered at” in 1.21.

His answer refers to the contents, ‘what he had answered,’ ‘the things he had said in reply.’

They were silent, or, ‘they said nothing more,’ ‘they became speechless,’ is a resultative clause: ‘so amazed that they fell silent.’

Quoted with permission from Reiling, J. and Swellengrebel, J.L. A Handbook on the Gospel of Luke. (UBS Handbook Series). New York: UBS, 1971. For this and other handbooks for translators see here . Make sure to also consult the Handbook on the Gospel of Mark for parallel or similar verses.