2 Corinthians 11:13-15

13Those people are false apostles. They do not work in an honest way. They try to make people think that Christ has sent them as his apostles.

14That should not surprise you! Even Satan can change himself to look like an angel who belongs to the light.

15So do not be surprised when Satan's servants do the same thing. They can also seem to be serving God. They may seem to be doing good things, but really what they do is bad. So God will punish them in the end.