Messianic rabbi Jonathan Cahn's keynote address at the January Presidential Inaugural Breakfast went viral on YouTube shortly after its posting. The video has garnered over 100,000 views, gaining worldwide attention for its bold outcry for America to return to God.

Though the its controversial message initially received some suppression on the Internet, its popularity continued to grow. Many have called it "the most important and powerful clip on YouTube ever."

In the video, Cahn, author of the New York Times best-seller The Harbinger, addressed U.S. senators and congressmen at the historic Marriot Wardman Park in Washington. 

"We must sound the alarm that must be sounded," Cahn stated in his keynote address at the interdenominational, bipartisan event. "We must address what must be addressed, and so the message now will not be politically correct. Nor will it be political. It will be biblical. It will be true. And wherever it falls, let it fall.

"I will not hold back," he continued. "And if I offend you, I apologize that I cannot apologize for offending you. Without truth there is no love. On a day that so embodies the future course of this nation, it's critical that we both pray and speak the truth."

Cahn detailed what he believes are the prophetic parallels between ancient Israel and modern-day America.

"As the people of ancient Israel, in the midst of their blessings, committed a fatal error, so have we," he continued. "We too, as a nation, have turned from God. We too, as a nation, have removed Him from our lives. Step by step we too have ruled Him out of our culture, out of our government, out of our economy. We too have ruled Him out of the instruction and lives of our children. We too have made God a stranger. And as we have driven God from our national life, we have brought in other gods and idols to replace Him—gods of sensuality, violence, wealth, carnality, sexual promiscuity. And as did Israel, so too we have abandoned the ways of God and the laws of God for the ways of immorality."

The Harbinger documents parallels between events in the U.S. since 9/11 and Israel's history after the nation turned from God. Told in narrative form, the book unfolds how nine signs or harbingers reveal God's judgment.

Published Jan. 3, 2012 by Frontline/Charisma House, The Harbinger has sold more than 1 million units and charted for 56 weeks on the New York Times and 55 weeks on USA Today's Top 150 Books. It has also had strong showings on best-seller lists by CBA and the Evangelical Christian Publishers Association.

Click here to see the video from the Presidential Inaugural Breakfast.