Sen. Rand Paul, R-Ky., asked Iranian President Hassan Rouhani to release Pastor Saeed Abedini, an American pastor imprisoned in Iran since 2012, in a letter that warned Abedini's jailors not to let him die.

"I must point out that if something were to happen to Pastor Abedini while he is incarcerated, any good will forged over the past few months would likely evaporate," Paul wrote in the Jan. 24 letter. "Conversely, granting clemency to Pastor Abedini and allowing him to return to the United States would do much to create a positive atmosphere that would reflect well on future discussions."

Paul asked Rouhani to release Abedini after meeting with Naghmeh Abedini, the pastor's wife, who has worked to keep the United States government focused on securing her husband's release.

"She is very concerned for her husband’s well-being," Paul wrote. "His health is deteriorating and he is apparently under constant threat of harm from both prison personnel and other inmates at Rajaei Shahr prison."

Jordan Sekulow, executive director of the American Center for Law and Justice, which represents Naghmeh Abedini, sees "a glimmer of hope" in Abedini's case, as the Iranian foreign minister told CNN that the Iranian judiciary could conceivably decide to give Abedini clemency.

"Could Iran be willing to give Pastor Saeed clemency? Could it be willing to release him to return to his wife and two children here in the U.S.?" Sekulow wrote. "One thing is for sure: Pastor Saeed's release would be a monumental humanitarian gesture for Iran. Clemency would give Iran the opportunity, within their own judicial system, to release Pastor Saeed and show the world that it is serious about changing its human rights record."