The meaning of ʻIlliyoon and Sijjeen
20-12-2015 | IslamWeb
Question:
Assalaamu alaykum. We know that during the journey of the soul after death, if the deceased is a believer, Allaah will command that he be written in ‘Illiyyoon, and if he is a disbeliever, that he be written in Sijjeen (as mentioned in Surah Al-Mutaffifeen). What are ‘Illiyoon and Sijjeen? Is ‘Illiyoon a place in Paradise and Sijjeen a place in the Hellfire? Or is ‘Illiyyoon a registry of the deeds of the believers and Sijjeen a registry of the deeds of the disbelievers? Or is it both, meaning that ‘Illiyoon is a registry of the deeds on the believers in Paradise and Sijjeen is a registry of the deeds in the Hellfire? I know that you may refer me to fatwa #6238, but it really does not answer the above question. May Allaah reward you.
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ʻalayhi wa sallam, is His slave and Messenger.
We usually refer the questioner to a previous fatwa on the website if the answer of his inquiry is underlined therein instead of reanswering the same question, thus saving time and effort. You should know, dear questioner, that there is no fatwa on our website with the number mentioned in your question.
As for your question about the meaning of the word (ʻIlliyyoon), it was said that it refers to Paradise, as narrated by ʻAtaa’ on the authority of Ibn ʻAbbaas 
. It was also said that it means the seventh heaven, where the souls of the believers shall be in the Hereafter, as also reported on the authority of Ibn ʻAbbaas and Mujaahid. It was also said that ʻIlliyyoon connotes elevation and sublimity, signifying high position and ascending and rising, as narrated on the authority of Al-Hasan 
.
Ibn Katheer wrote, “The apparent view is that the term ʻIlliyyoon is derived from ʻuluw, meaning 'highness'. The more something ascends and rises, the more it becomes greater and vaster...”
There is no contradiction between the reported interpretations; the believers shall dwell in Paradise on the Day of Judgment, and Paradise is located above the seventh heaven, and their souls shall be in the seventh heaven during Al-Barzakh (the period between death and resurrection). They shall be in ʻIlliyyoon in the Barzakh and on the Day of Judgment.
As for the term (Sijjeen), it was said that it means the seventh earth according to Mujaahid and Qataadah 
. It was also said that the term is associated with baseness and ignominy; it refers to the records in which the acts of all the evildoers are written, and they will be in a low and mean place, the lowest of the low, as held by Al-Hasan . It was also said that it means that the evil doers will experience utter loss, as narrated on the authority of 'Ikrimah . Another interpretation suggests that the evildoers will be imprisoned in straitened circumstances. The word Sijjeen is derived from the mother word (Sijn) meaning prison. There also is no contradiction among these interpretations because the records in which the acts of the evil doers will be written will be preserved in the seventh earth, in the lowest of the low; it connotes severe imprisonment in a dreadful and narrow place.
Ibn Katheer wrote, “The final destination of such evil doers will be Sijjeen, a narrow prison ... The most likely correct view is that the term Sijjeen is derived from the word sijn (prison). The lower something becomes, the narrower it becomes and the more something rises, the more it widens...”
Allaah knows best.