What is the difference between the words "الرجس" (al-rijs) and "الرجز" (al-rijz), what is the connotation of each, and does either of them refer to the meaning of "impure"?

Scholars differed concerning al-rijz and al-rijs: Are they one word whose letter sin was replaced by zay, or are they two words with the same meaning, namely filth, or do their meanings differ? Al-rijz may refer to torment, and it may refer to filth, whereas al-rijs is used for impurity and filth. This is supported by Quranic verses and Prophetic traditions.