Is it permissible to call “The prayer is a gathering” for the prayer for rain?

Question:
May Allah reward you, Honorable Shaykh. This questioner says: There is a mosque in one of the villages where the caller announces “The prayer is a gathering” for the prayer for rain, because the people do not attend. When he calls out with the loudspeaker, they attend. Is his action valid?

Answer:
No, it is not valid. This is not said except for the eclipse prayer only. As for the prayer for rain, it is not called for. Nor for the festival prayer, and the festival prayer is more emphasized than the prayer for rain; it is a collective obligation, yet with this, it is not called for. We do not innovate anything and say this will gather the people, or we do not innovate anything.