p. 181
यमं त्वेके मृत्युमतोऽन्यमाहुरात्मावासममृतं ब्रह्मचर्यम् ।
In plain words
Some say Yama is simply death. Others say what is other than death — living in the Self, the immortal — that is brahmacarya.
Close to the Sanskrit
But some call Yama death; [others] call that which is other than this the dwelling in the Self, the immortal, brahmacarya.