According to an authentic Hadith, the Prophet was once leading the prayers while sitting due to some physical illness. It so happened that some muqtadis prayed standing. On finishing the prayers, the Messenger of Allah said that Imam is there to be followed, if he prays standing the Muqtadis should pray standing, if he prays sitting the Muqtadis too should pray sitting. In the light of this Hadith one may ask if it is necessary to do rafa-yadain behind a Wahabi Imam?