John 18:7

Again therefore he asked them, Whom seek ye? And they said Jesus of Nazareth. Jesus answered, I told you that I am he; if therefore ye seek me, let these go their way: that the word might be fulfilled which he spake, Of those whom thou hast given me I lost not one.

If the arrest had not been prevented, some, perhaps all of them would have been lost.

Whom seek ye ... ? The shock of what had just happened was still upon them all; and, under the circumstances, they readily agreed to Jesus' request of exemption from arrest for his apostles. John 18:9 strongly suggests that this miracle, like all the others, was not for Jesus' personal benefit, but for the benefit of others.