إني داع فآمنوا
Innī dāʿin fa-āminū
Topic
“I am about to supplicate, so say Amin”: the imam’s call for the congregation to join his prayer.
What it means
The words mean “I am a supplicant, so say Āmīn.” The imam says them at the end of the sermon or after the prayer, before reciting supplications, to ask those who are present to join him by saying Āmīn after each invocation. Āmīn means “may it be so” or “answer, O God”. The phrase belongs to the customs of the Friday sermon and congregational prayer, and the text does not come from the Quran or a fixed hadith. Muslims find a basis for the practice in the value that their tradition gives to supplication together, and in the Prophet’s example of saying Āmīn after reciting al-Fātiḥa. Practice differs by region.
Term and Arabic as listed in Ismail al Faruqi, Toward Islamic English (International Institute of Islamic Thought, 1995), p. 56, listed as INNĪ DĀ‘IN FA AMMINŪ.. The definition is restated here.