Luke 22:6

So he consented, and began looking for a good opportunity to betray Jesus to them [at a time when He was] separated from the crowd [because the people might riot or stop them from seizing Him].

Matthew 26:5

But they said, “It must not be during the festival (Passover), otherwise there might be a riot among the people.”

Mark 14:2

but they were saying, “Not during the festival, for the people might riot.”

Treasury of Scripture Knowledge

Summary

And he promised, and sought opportunity to betray him unto them in the absence of the multitude.

In the absence of the multitude

Bible References

In the absence of the multitude

Matthew 26:5
But they said, “It must not be during the festival (Passover), otherwise there might be a riot among the people.”
Mark 14:2
but they were saying, “Not during the festival, for the people might riot.”