Shlok 80

Upavaasadine Tyajya Diva Nindra Prayatrataha       |
Upavaasstaya Nashyenmaithuneneva Yanruram       ||80||

A day spent sleeping destroys the Vrata.  By sleeping, the day is wasted away, which should really be used in praise of God.  When sleeping, the fast becomes easier to keep and for these reasons, such days should not be passed by sleeping.

Upavassya Dine Ekadashyadau Praischitarthopavasdivase                           |
Cha Diva Nidra Prayatnataha Sarvaprakarera Tyaja Na Kartavyetyarthaha            || 

‘One should not sleep during days of Upavaas for Ekadashi etc. and on days of Upavaas for Prayaschit.’  Such days spent sleeping, destroys the Vrata of Upavaas which is similar to that of sexual indulgence.  Deval Smurti explains: Upavaasaha Pranasyeta Diva Swaapacha Maithunad - ‘Sleeping during the day and sexual indulgence destroys the fruits of Upavaas.’  Thus both are considered equivalent.

During all Vratas, Brahmcharya (celibacy) is considered to be important.  Those Vratas performed without Brahmcharya are fruitless.  Puranas and Dharma Shastras explain that Brahmcharya is destroyed through the ejaculation of semen from the body.  Ejaculation is caused through the association of a woman or by dreaming, say Rishis.  For such reasons, on such days, one should stay aloof of the company of women and also prevent themselves from dreaming of situations involving the company of women in this way.  Thus, one should spend the day with their senses focussed away from such desires.  If by accident, one does release semen on such a Vrata day, one should perform Avakirni Prayaschit, as explained later.

One should understand that sleeping during the day is prohibited ordinarily for all days (as explained earlier (Sh.15).  Sleeping on Ekadashi and other Vrata days is more so prohibited.  Many believe that the Lord here forbids sleeping if Upavaas is performed on Vrata days and so if Ektanu (eating just once) is performed then there is no problem in sleeping.  This is absolutely incorrect.  One should not sleep during the day nor indulge in sexual activities if the Vrata is kept, regardless of whether Upavaas or part Upavaas was performed, as these will surely destroy the Vrata.  Now Lord Swaminarayan explains which Vrata days are worthy of praise and observance.