Read Luke 20:26 Using Other Translations
And they could not take hold of his words before the people: and they marvelled at his answer, and held their peace.
And they were not able in the presence of the people to catch him in what he said, but marveling at his answer they became silent.
So they failed to trap him by what he said in front of the people. Instead, they were amazed by his answer, and they became silent.