He said he and his audience were "under siege."
The sentiment resonates with evangelicals, who often charge that American politics and culture have shunted them aside. Across the divide, other parts of the electorate accuse conservative Christians of using the government to impose their values on others.
So far, Trump's most loyal supporters seem to care more about his positions on their core issues than on the questions about his leadership raised in Comey's testimony.
Trump in his remarks did not directly refer to Comey's testimony, which riveted much of the nation that morning. But he did — after he read a verse from the Book of Isaiah — denounce his political enemies as lying obstructionists.
"Learn to do right, seek justice, defend the oppressed. Take up the cause of the fatherless, plead the case of the widow," he said, quoting the biblical verse. Then he added:
"The entrenched interests and failed bitter voices in Washington will do everything in their power to try and stop us from this righteous cause, to try to stop all of you. They will lie, they will obstruct, they will spread their hatred and their prejudice, but we will not back down from doing what is right.
"Because, as the Bible tells us, we know the truth will prevail," he added.
To sustained applause, Trump listed what he had done in his four months as president to help fulfill conservative Christians' agenda:
• He nominated a Supreme Court justice, Neil Gorsuch, whom he described as a worthy successor to conservative hero Antonin Scalia.
• He blocked federal funds for nonprofits that perform abortions abroad.
• And he touted his executive order that last month directed the IRS to tread lightly with the federal regulation that bars pastors from politicking in the pulpit.
"The people that you most respect can now feel free to speak to you," Trump said. "That was a big deal. And it was a very important thing for me to do for you and we're not finished yet, believe me.
"As long as I am president no one is going to stop you from practicing your faith or from preaching what is in your heart."
The legal stricture in question, known as the Johnson Amendment, had hardly been enforced, and many pastors — including evangelicals — say they don't feel it wise to endorse candidates from the pulpit. But some evangelical leaders told Trump that abolishing the amendment — only Congress can actually get rid of it — was a priority for them.
White evangelical Christians voted for Trump in November by larger margins than any other religious group — 81 percent.