Republicans are slamming Speaker Mike Johnson for what they say was an overly religious sermon delivered at a weekend G.O.P. retreat, according to a new report. Johnson (R-L.A.) was supposed to speak to Republican lawmakers at the Mandarin Oriental Hotel in Miami about holding onto the party’s House majority, but sources told Politico the topic was less tactics and more tenets. “I’m not at church,” one source told Politico. “The sermon was so long.” Want more breaking political news? Click for the latest headlines at Raw Story. Johnson, a devout Christian, reportedly bemoaned declining church …