Surah Az Zukhruf Tafseer

فَاخْتَلَفَ الاْاَحْزَابُ مِن بَيْنِهِمْ

But the sects from among themselves differed.

means, they differed and became parties and factions, some who stated that he (Isa) was the servant and Messenger of Allah -- which is true - while others claimed that he was the son of Allah or that he himself was Allah -- glorified be Allah far above what they say.

Allah says:

فَوَيْلٌ لِّلَّذِينَ ظَلَمُوا مِنْ عَذَابِ يَوْمٍ أَلِيمٍ

So woe to those who do wrong from the torment of a painful Day