Matthew 26:5

‘But they said, “Not during the feast, lest a tumult arise among people.” '

They had the sense to recognise that it could not be done during the Feast as the public arrest of One Whom many saw as a prophet would undoubtedly arouse the fanaticism of many in the crowds. Indeed those sent to arrest Him might even be stoned. It would thus need to be postponed until after the Feast. They could not afford trouble during it, with the governor's eagle eye on them. And the problem was that in an overcrowded Jerusalem Jesus always seemed to be surrounded by crowds. They thus had no way of getting at Him while He was alone with only His disciples for company. They knew that such a situation might sometimes happen at night, but then they had no idea where He was.

Note the deliberate contrast between Jesus knowing when it was going to happen, and the uncertainty of these men who had no idea when they would be able to do it. (It would be the treachery of Judas that would make them suddenly change their minds, when like minds came together). Note also their hatred which is in such contrast with the woman about to be described. They simmered in fury, she glowed with love,