A Ted Cruz administration would repeal Obamacare, abolish the IRS, institute a flat tax and “end the president’s unconstitutional amnesty,” the Texas senator said during his first speech Monday as a declared Republican presidential candidate in front of students at Liberty University in Virginia. Throughout the speech, Cruz highlighted his faith to the crowd at the private Christian school and encouraged evangelical Christians to head to the polls next year.

“God’s blessing has been on America from the very beginning of this nation, and I believe God isn’t done with America yet,” Cruz said. He urged the crowd to “join a grassroots army” for his campaign. "I believe in the power of millions of courageous conservatives rising up to reignite the promise of America. And that is why today I am announcing that I'm running for president of the United States."

Cruz’s other loudest applause line came on Israel, where he criticized President Barack Obama for not meeting with Israeli Prime Minister Benjamin Netanyahu when he addressed Congress earlier this month. “Instead of a president who seeks to go to the United Nations to end-run Congress and the American people, imagine a president who says I will honor the Constitution and under no circumstances will Iran be able to acquire a nuclear weapon,” he said.

Cruz attempted to appeal to both evangelical and youth voters, saying both voting blocs don’t turn out enough to the polls. “Imagine instead millions of people of faith all across America coming out to the polls and voting our values,” he said. On young people, he added, they are “worried about the future. Imagine them coming together saying, ‘We will stand for liberty.’”

Hours before his speech, Cruz announced he was running in a tweet and short video sent out shortly after midnight on Monday. He is the first candidate from a major political party officially to enter the 2016 race. Other presumed candidates have only launched presidential exploratory committees or similar vehicles, such as ex-Florida Gov. Jeb Bush and retired neurosurgeon Dr. Ben Carson.

Cruz, a 44-year-old first-term senator elected in 2012, gained a national reputation for being the Republicans’ harshest critic of Obamacare. He held a 21-hour filibuster on the Senate floor against Obamacare and was a key figure in the 16-day government shutdown in 2013. The Texas senator has also led the fight against Obama’s executive actions on immigration.

Before the Senate, Cruz, a lawyer, served as solicitor general for Texas, where he represented the state in cases to the Supreme Court. Cruz argued nine cases before the higher court.