What is the ruling on some one reciting or pronouncing the letters of the Qur'an wrongly for example for " Wathakoonul Jibalu" pronouncing Watakoonil Jibalu".

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions. The Muslim should know all the rules related to the mode and place of articulation of letters so that he does not change their pronunciation or the meaning of the words they form. Studying such rules is compulsory within the ability of the person. The person should endeavor to read Qur'an and recite it in the way and manner the Prophet (Sallallahu Alaihi wa Sallam) taught it to his companions. Anyone who does not do that, yet it is possible for him to do so, commits a sin. We remind the dear questioner that the evident mistake in Fatihah nullifies the prayer. Allah knows best.