What is the evidence for the invalidity of the prayer, ablution (wudu), ritual bath (ghusl), Hajj, and all other acts of worship performed by someone who carries out the physical form without knowing their obligatory acts (furood), Sunnahs, and rulings, and what must a Muslim learn concerning the matters of his religion?

What Al-Tattā'ī mentioned regarding Al-Awfī concerning the invalidity of prayer only applies if there is a defect in it. However, if it is performed correctly without any defect, then it is valid. Al-Dasūqī clarified that the prayer is valid as long as it is free from defects, even if the worshipper believes that all its parts are obligatory, or that they are all Sunnah, or believes that an obligation is Sunnah and vice-versa, and this is the relied-upon opinion. This is supported by the Prophet's (peace be upon him) saying: "Pray as you have seen me praying." The same applies to ablution (wudu'), ritual bathing (ghusl), and Hajj; they are valid if the Muslim performs them in their correct manner without any defect. It is obligatory for a Muslim to learn what Allah has made individually incumbent upon him, such as creed and the rulings of prayer and fasting.