Answer: Pahlavi regime arrested Imam Khomeini for the first time at 3:30 a.m. in the 15th of Khordad 1342 (5, June, 1963). The reason was his pounder and epical lecture in the 13th of Khordad on the occasion of Ashora (Moharam 1383). In his lecture, he presented Shah (king) and Israel as the main causes of concern in Iran. Broadcasting the news of Imam Khomeini's detention raised people's objections and caused a great revolution on the 15th of Khordad which was repressed by the regime officers. Imam Khomeini spent 10 days in prison and was finally let out of jail in the 18th of Farvardin 1343, since the government was under the great pressure of public thought.