لَّقَدْ كَفَرَ الَّذِينَ قَالُواْ إِنَّ اللّهَ ثَالِثُ ثَلَثَةٍSurely, they have disbelieved who say:"Allah is the third of three."Mujahid and several others said that;this Ayah was revealed about the Christians in particular.As-Suddi and others said that;this Ayah was revealed about taking `Isa and his mother as gods besides Allah, thus making Allah the third in a trinity.As-Suddi said, "This is similar to Allah's statement towards the end of the Surah,وَإِذْ قَالَ اللّهُ يَا عِيسَى ابْنَ مَرْيَمَ أَأَنتَ قُلتَ لِلنَّاسِ اتَّخِذُونِي وَأُمِّيَ إِلَـهَيْنِ مِن دُونِ اللّهِ قَالَ سُبْحَانَكَAnd (remember) when Allah will say:"O `Isa, son of Maryam! Did you say unto men:`Worship me and my mother as two gods besides Allah' He will say, "Glory be to You!" (5:116)Allah replied,وَمَا مِنْ إِلَـهٍ إِلاَّ إِلَـهٌ وَاحِدٌBut there is no god but One God.meaning there are not many worthy of worship but there is only One God without partners, and He is the Lord of all creation and all that exists.Allah said next, while threatening and admonishing them,وَإِن لَّمْ يَنتَهُواْ عَمَّا يَقُولُونَAnd if they cease not from what they say,their lies and false claims,لَيَمَسَّنَّ الَّذِينَ كَفَرُواْ مِنْهُمْ عَذَابٌ أَلِيمٌverily, a painful torment will befall the disbelievers among them.in the Hereafter, shackled and tormented.Allah said next,أَفَلَ يَتُوبُونَ إِلَى اللّهِ وَيَسْتَغْفِرُونَهُ وَاللّهُ غَفُورٌ رَّحِيمٌ