President Donald Trump unleashed several attacks against who he at times referred to as “radical left lunatics,” during his eulogy for Charlie Kirk at a memorial service on Sunday. And one Christian leader says he’s “deeply concerned.”

The president was one of the many speakers who were in attendance at the service, which was held at the State Farm Stadium in Glendale, Arizona. Kirk, an influential right-wing activist who founded conservative youth organization Turning Point USA, was shot and killed while speaking at Utah Valley University on Sept. 10.

In his 40-minute tribute for Kirk, Trump closed out the service by talking about the late activist’s journey in politics, their friendship, and the 31-year-old’s influence on energizing young conservatives on college campuses. But he did not miss the opportunity to attack his opponents, highlight his political goals and controversial tariff policies, and to make clear that he apparently has no intention of unifying the nation, as the country grapples with extreme divisiveness and attacks on free speech in the wake of Kirk’s killing.

Trump said in his speech that he sometimes describes people on the left as “radical left lunatics.” He referenced ABC’s decision to pull Jimmy Kimmel’s late night show after the host criticized conservatives’ reactions to Kirk’s killing. The president mocked Kimmel, without saying his name, insisting that he “had no talent.” (On Monday, Disney announced that it was bringing “Jimmy Kimmel Live!” back on air.)