2 Peter 2:10-11:

But chiefly them that walk after the flesh in the lust of uncleanness, and despise government. Presumptuous are they, selfwilled, they are not afraid to speak evil of dignities.
Whereas angels, which are greater in power and might, bring not railing accusation against them before the Lord.

See also:

Avoiding Fear of Satanic Retaliation
How to Deal with the Devil
How NOT to Deal with the Devil