The president referred directly to the 2015 attack at the church.
Biden's remarks were interrupted by protesters chanting "ceasefire now," referring to Israel's assault on Gaza that has killed more than 23,000 people. Biden said he has been working with the Israeli government to "get them to reduce and significantly get out of Gaza."
Some audience members chanted "four more years" when Biden took to the pulpit and again as those protesters were led away.
Biden described Trump as a threat to democracy, citing the deadly attack on the U.S. Capitol by Trump supporters in 2021 hoping to overturn the Republican's election loss.
Recent polling has shown Trump beating Biden, a Democrat, in swing states that will determine who wins the White House this year, and a Reuters/Ipsos poll in December showed a rematch would be close.
