ויקרא, פרק כ״א, פסוק י״א

The High Priest is held to an absolute standard of purity, elevating him above ordinary human mourning practices. He is forbidden from coming into contact with death under any circumstances, even when it involves his closest relatives whom he is obligated to honor during their lifetimes [אבן עזרא, ביאור שטיינזלץ].

This restriction extends beyond the physical body itself. On a simple level, the concept of a soul is used to describe the actual corpse [אבן עזרא, אבי עזר]. However, the primary approach among commentators is that this alludes to human blood, as life and the soul are entirely dependent on it. Consequently, even a minimal amount of blood that spills from a deceased person carries the exact same impurity as a whole corpse. The laws of impurity apply whether this minimal amount of blood comes from a single body [לבוש האורה, שפתי חכמים], or if it is combined from the blood of two different deceased individuals [מזרחי, תורה תמימה, מלבי״ם, ברטנורא].

The boundaries of this purity are strictly defined to include both direct contact and sharing physical space. The High Priest is prohibited from entering any enclosed structure, such as a tent or a house, that contains a deceased person [הכתב והקבלה]. This restriction against entering a shared space is treated as a distinct prohibition from the ban on physical contact, which applies even out in an open field without a roof [מזרחי, ביאור יש״ר].

Although the High Priest is banned from contacting any dead body, his father and mother are specifically mentioned to highlight a profound moral exception. While he may not defile himself for his own parents, there is one unique scenario where he must compromise his purity. He is obligated to care for an abandoned corpse with no one else to bury it. Attending to the critical needs of a neglected fellow Jew overrides even the highest spiritual duties of the High Priest, even if this occurs in the middle of the Yom Kippur service inside the Holy of Holies [חומש קה״ת].

The specific mention of both parents also establishes precise guidelines regarding his interactions with them while they are still alive. Drawing a legal parallel to the laws of a Nazirite, commentators explain that while the High Priest cannot become impure for his parents' death, he is permitted to attend to them during their lives if they suffer from conditions like leprosy or abnormal bodily discharges [מזרחי, תורה תמימה, גור אריה]. From a deeper spiritual perspective, the mention of the High Priest's parents serves as a subtle tribute to Aaron's own parents, Amram and Yocheved. According to tradition, they passed away in a state of absolute purity without the Angel of Death having any power over them [שפתי כהן].