[Wilford Woodruff vision of Satan]
... I repaired to the house of the LORD in company with Elders Milton Holmes, & Joseph B Nobles for the purpose of worshiping God. We entered one of the stands within the veils & fell upon our knees & Satan appeared also but not to worship God but to deprive us of the privilege. Satan strove against us with great power by tempting & otherwis. He at one time drove me from my stand while I was striving with my brethren to enter into the visions of heaven.
Notwithstanding his apparent victory good grew out of it for by going into the outer Court I there found Elder Freeman Nickerson an aged father in Israel who was faithful & Prayed to God alway. I solicited him to Join us in prayer that we might gain a victory over Satan & get a blessing at the hand of God. He joyfully accepted the invitation & we again entered the stand being four of us in number of one accord in one place. We had great cause to be united in heart. ...
We fell upon our Knees & began to cry unto God. Satan departed, tempation found no place in our harts The power of God rested upon us & we were baptized with the Holy Ghost & the Spirit of God was like fire shut up in our bones. We were immersed in the liberty of the sons of God. Many great things were shown unto us. The power of God & the Spirit of prophesy & revelation rested upon us. I arose & Proclaimed many Glorious thing upon the heads of my beloved brethren that were present which were dictated in my heart by the Holy Spirit. And I Willford testify in the name of Jesus Christ that many precious things were shown me concerning my brethren by the Holy Spirit in prophecy & revelation. Our hearts were made glad & we went our way rejoicing. +
[Source: Wilford Woodruff's Journal: 1833-1898 Typescript, Volumes 1-9, Edited by Scott G. Kenney, Signature Books 1993, http://amzn.to/newmormonstudies]