Quoting from an article hosted at kamakoti.org "VEDA DHARMA SASTRA PARIPALANA SABHA (Regd.), Kumbhakonam, Publication No. 50":
MORNING ROUTINE
Everyone should get up from bed in Braahma muhurtham,i.e. five nazhigas (two hours) before sunrise, i.e. 4 a.m. If we sleep beyond that time, we will not only lose the merit we have, but also attract the curse of Pitrus. During Sandhya times, taking food, enjoying sex, sleep, reading- these four are prohibited. As soon as we get up from bed, we should see auspicious objects while waking up. We should contemplate on God, Rishis and Punyatmas (holy persons). We should then go to a deserted place at least 100 feet away in east, south or north direction, keep water and soil, conceal head with cloth, face north in daytime or south in night time and pass stools silently. Passing stools and urine should not be done in front of Agni, woman, brahmana, Guru and cow and in water, ditches of animals, peaks of hills, temple premises, banks of river, under a tree, areas of fodgrains and facing temple. If urine and stools come into contact with any part of the body, that part should be cleaned with soil. Cleaning should be done first for stools, then urine, followed by left hand, both hands and feet. After cleaning thus, brushing teeth should be done. Brushing of teeth should not be done with soil, stone or ash; it may be done using tooth powder not mixed with lime and tooth stick of banyan or neem; it should not be done with index finger. But brushing teeth should not be done on days of Parva (Amavasya/ Purnima) and Sankramana with sticks. All these instructions can be very easily observed, but we fail owing to laziness, negligence and insincerity; there is nothing impossible about it. If we analyse the instructions in the Sastras, we find that they are meant for our good and health free from disease. Hence we should follow the instructions in Sastras as far as possible. Formerly nobody used to dirty the waters. Now all sit in water, clean themselves after stools/ urine, brush their teeth there itself and spit and rinse their mouths and thus dirty the waters.
Daily Routine
There are three types of benefits for the instructions given in our Sastras. One is, benefit experienced here and now; the second, to be experienced in the next birth; the third, benefit in both ways. This is also called Drishta phala (seen benefit); Adrishta phala (unseen benefit); Drishtaadrishta phala (Seen and unseen benefit). Forgetting the Unseen benefit of purifying (after stools/ urine), the seen benefit is experienced by all who follow. It is saddening that many of us follow the practices from cold countries without bothering about their applicability. It is the Apaana air that expels stools. At that time, bad smell is seen in the place. Is it not necessary to wash with soil and water to rid of the bad smell? In what way is one, who does not wash after passing urine, is superior to animals? By washing feet frequently, the heat in the head reduces. By rinsing, the disease in teeth goes away.
Rinsing, Aachamanam and cleaning of teeth
After cleaning private parts with soil and water, one should tie the dhoti ‘kachcham’ properly, if loosened, tie the hair and rinse the mouth. Spitting the water should be done on the bank of river and that place should also be washed with water. While rinsing, one should sit and spit on the left side, as right side is of Devas. Rinsing of mouth has been specified to be four times after passing urine and 16-18 times after passing of stools.
My question is about the bold portion. Which scripture states that on our right side always reside the Devas? Also what about the left side? Which beings reside on that side?
