Matthew 14:9

‘And the king was grieved, but for the sake of his oaths, and of those who sat at meat with him, he commanded it to be given.'

The king was ‘grieved'. He might hate John but he respected him and was even afraid of him. This was the last request that he had expected. But because of the strength of his oath, which he no doubt now regretted, and in order to maintain face in front of all the great and prominent men who had heard his oath, he commanded that it should be done as she said. Legally he could have withdrawn from his oath under Jewish Law, but his guests were not Jewish, and to them a prophet would not have been worth bothering about, so that Herod may well have recognised that they might well despise someone who counted an odd prophet as being worth more than a man's oath.

‘The king.' An honorary title (see above). Matthew may well have intended it to be sardonic. This man wanted to be king, and yet he behaved like this.