When one awakens in the morning from one’s sleep, one must wash one’s hands and recite the blessing, “Baruch Ata Hashem Elokeinu Melech Ha’Olam Asher Kideshanu Bemitzvotav Vetzivanu Al Netilat Yadayim” (this law is discussed in Berachot 60b). The order of this washing is, as follows: First, one should take the washing vessel in one’s right hand and when it is full, one should transfer it to one’s left hand and use it to pour water on one’s right hand. Then, one should transfer the vessel into one’s right hand and use it to pour water on one’s left hand. This process should be repeated three times. After doing so, one should then recite the blessing of “Al Netilat Yadayim,” and then proceed to dry one’s hands.
There are several reasons given for why one must wash one’s hands in the morning:
The first reason is based on what the Gemara in Masechet Shabbat (108b) teaches us that an evil spirit rests upon one’s hands at night and it does not depart until one properly washes one’s hands. This does not have to do specifically with sleep; rather, it is something linked with the essence of nighttime.
The second reason is discussed in the holy Zohar (Parashat Vayeshev) that when one goes to sleep at night, the soul departs from one’s body (to a certain degree) and one tastes the taste of death causing an evil spirit to rest upon one’s body. When the soul returns to the body upon awakening from one’s sleep, the evil spirit still rests on one’s hands and in order to remove it, one must wash one’s hands properly.
The third reason is quoted by the Rosh in his rulings (Berachot Chapter 9, Section 23) where he writes that since one’s hands are continuously in motion even when one sleeps, it is impossible that one did not touch unclean places during one’s sleep; thus, one must wash one’s hands upon awakening.
The fourth reason is quoted in the responsa of the Rashba (Chapter 191) where he writes that one is considered a new creation in the morning, as the verse (Eicha, Chapter 3) states, “Renewed in the mornings, great is your belief.” Thus, we must thank Hashem who created us in His honor in order to serve Him and bless in His name.
The fifth reason is quoted by Rabbeinu David Abudirhem who writes that just as the Kohanim were obligated to wash their hands before performing the holy service in the Bet Hamikdash, so too, one must sanctify one’s hands upon awakening from one’s sleep before beginning one’s service of Hashem so that one may serve Hashem with clean hands.
Halachically speaking though, it would seem that there are several halachic ramifications involved depending on the different reasons we have mentioned. For instance, if one stayed awake throughout the entire night, according to the words of the Gemara quoted in the first reason, one would certainly still need to wash one’s hands in the morning, for the nighttime hours have nevertheless elapsed. Nevertheless, according to the words of the Zohar mentioned in the second reason and according to the ruling of the Rosh mentioned in the third reason, this person would not have to wash his hands, for hand washing is only necessary when one sleeps, and this person did not. Similarly, a distinction would likewise exist regarding one who slept during the day, for according to the Rosh’s reasoning of one’s hands constantly being in motion, this would certainly apply to sleeping during the day as well, whereas according to the reasoning of the Gemara (and possibly according to the Zohar as well, see Bet Yosef Chapter 4 who is uncertain about this) the obligation to wash one’s hands cannot apply during the day, for the evil spirit does not rest on one’s body during the day.
Thus, halachically speaking, if one remained awake all night or slept during the day, one should wash one’s hands in the morning or when one awakens from one’s sleep. Nonetheless, since it is doubtful in this situation whether or not one is obligated to recite a blessing, one should not recite a blessing on this washing in accordance with the rule of “When in doubt regarding a blessing, do not bless.”