Understanding the words of the Holy Book
Al-Raghib al-Asfahani
Classical reference for Quranic vocabulary
إِنَّ ٱللَّهَ وَمَلَٰٓئِكَتَهُۥ يُصَلُّونَ عَلَى ٱلنَّبِىِّ ۚ يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ صَلُّوا۟ عَلَيْهِ وَسَلِّمُوا۟ تَسْلِيمًا
God and His angels shower their blessings on the Prophet. O believers, you should also send your blessings on him, and salute him with a worthy greeting.
Al-Ahzab 33:56