2 Corinthians 11: 4, 13-15 (KJV)
4 For if he that cometh preacheth another Jesus, whom we have not preached, or if ye receive another spirit, which ye have not received, or another gospel, which ye have not accepted, ye might well bear with him.
13 For such are false apostles, deceitful workers, transforming themselves into the apostles of Christ.
14 And no marvel; for Satan himself is transformed into an angel of light.
15 Therefore it is no great thing if his ministers also be transformed as the ministers of righteousness; whose end shall be according to their works.