Hebrews 4:15:

For we have not an high priest which cannot be touched with the feeling of our infirmities; but was in all points tempted like as we are, yet without sin.

See also:

Can I Just Command the Devil to Leave Me Alone?
Can I Get Healed of Alcoholism, Drug Abuse, Pornography and Homosexuality?
If We Have Authority over All Demons, Why Didn’t Paul Just Take Authority over the Thorn-in-the-Flesh Spirit?
Objection: God Wouldn’t Heal Paul’s Thorn in the Flesh
Objection: We Cannot Expect to Heal as Jesus Did Because We Are Not the Son of God