यदाकल्पः स्वक्रियायां व्याधिभिर्जरयाथवा ।
आन्वीक्षिक्यां वा विद्यायां कुर्यादनशनादिकम् ॥ २३ ॥
yada-when; akalpah-unable to act; sva-kriyayam-in one's own prescribed duties; vyadhibhih-because of disease; jaraya-or because of old age; athava-either; anviksikyam-in spiritual advancement; va-or; vidyayam-in the advancement of knowledge; kuryat-one must do; anasana-adikam-not take sufficient food.
When because of disease or old age one is unable to perform his prescribed duties for advancement in spiritual consciousness or study of the Vedas, he should practice fasting, not taking any food.