Pastors and other religious officials are generally free to say what they wish to their congregants. And many do, speaking out forcefully on a host of potentially inflammatory topics, including politics, abortion, race and gay marriage. But there's a line that should not be crossed: endorsing political candidates.
Congress passed an amendment to the U.S. tax code back in 1954 that barred 501(c)(3) organizations — tax-exempt groups such as churches and charities — from any political campaign activity. And over the last few decades, it has slightly strengthened this prohibition. Most recently, in 1987, Congress clarified the language to specify that it also pertains to making statements opposing political candidates [source: Musselman].
Many churches routinely ignore this law, instructing their congregations on who to vote for (or not to vote for) in upcoming elections. And at times, the Internal Revenue Service has indicated it will challenge these churches, potentially removing their exempt status, though in practice it rarely has. Churches can get around this restriction if they wish. For example, a pastor can endorse a particular candidate by speaking at the candidate's headquarters as an individual, not in an official capacity as pastor of a certain church. And if one candidate is invited to speak during a service, all should be invited as well [source: Reilly].