Revalation 13 is about the beast from out of the sea and the beast from out of the earth.
The beast out of the earth is the beast numbered 666.
The beast from the sea passage ends with this warning:
He who has an ear, let him hear.
If anyone is to go into captivity, into captivity he will go.
If anyone is to be killed with the sword, with the sword he will be killed.
This calls for patient endurance and faithfullness on the part of the saints.
This echoes the warning at the end of the passage about the beast out of the earth:
This calls for wisdom. If anyone has insight let him calculate the number of the beast, for it is man's number. His number is 666.
