The meaning is: when Allah is mentioned with His Oneness, they believe in Him without doubt.
Surat Ar-Ra'd from verse (29) to verse (31).
الْمَعْنى: إِذْ ذُكِرَ اللَّهُ بِوَحْدَانِيَّتِهِ، آمَنُوا بِهِ غير شاكين.
سُورَة الرَّعْد من الْآيَة (٢٩) إِلَى الْآيَة (٣١).
