وَبِكُفْرِهِمْ وَقَوْلِهِمْ عَلَى مَرْيَمَ بُهْتَانًا عَظِيمًا
And for their faithlessness, and their uttering a monstrous calumny against Mary,
Agha Ali Puya Commentary
Commentary on Quran 4:156
[Pooya/Ali Commentary 4:156] The Jews not only disbelieved in Isa but also spoke dreadful calumnies of Maryam, going to any length in accusing her of immorality. In the ancient Jewish "Life of Jesus" (the Toldoth Jeshu) it is written that she was seduced by Joseph, the son of Pandera, because she was under the impression that he was her betrothed. For this outrageous slander Allah had sealed their hearts (refer to the preceding verse).