Current opinion is that Yama is one sort of Death; the wearing out of the soul is said to be another sort; the pursuit of Brahman or selfknowledge is immortality. The god (Yama) rules the region of the Pitris, conferring blessings on the honest and curses on the dishonest.
रात्मावसन्नममृतं ब्रह्मचर्यम्। पितृलोके राज्यमनुशास्ति देवः शिवः शिवानामशिवोऽशिवानाम्॥