28 “Then, from that day forth, they took counsel together for to put Him to death. Jesus therefore walked no more openly among the Jews; but went thence unto a country near to the wilderness, into a city called Ephraim, and there continued with His disciples.” Not that there was any failure in His power, by which, had He only wished, He might have continued His intercourse with the Jews, and received no injury at their hands; but in His human weakness He furnished His disciples with an example of living, by which He might make it manifest that it was no sin in His believing ones, who are His members, to withdraw from the presence of their persecutors, and escape the fury of the wicked by concealment, rather than inflame it by showing themselves openly.
Source: Tractates on the Gospel of John (New Advent)