Religion seems to play little role in the life of Ivan Illyich. It is clear that he believes in God or some sort of higher existence, and yet he only really confronts God when it is clear that he is dying and there is no hope for him. He only takes communion in Chapter 11 at his wife's behest, and does experience some relief from this religious ceremony:
When the priest came and heard his confession, Ivan Illyich was softened and seemed to feel a relief from his doubts and consequently from his sufferings, and for a moment there ame a ray of hope. He again began to think of the vermiform appendix and the possibility of correcting it. He received the sacrament with tears in his eyes.
However, this relief is short lived, as he is again confronted with the falsity of his wife and all that she represents and is forced to face the inevitability of his own death. Thus, the little mention that religion is given supports the deception and the "lie" that forces Ivan Illyich's family to continue as if nothing was happening and to try to ignore the fact of their father's death. It is interesting that in his final moments there is no mention of God, and the release that Ivan Illyich finds in the light that he sees instead of death does not come from religion but from the affection and love of his son.