Purification is something we do on the physical, mental, emotional, and spiritual levels. There are many ways of purifying. Since our culture does not include purifying rituals as part of our everyday lives, we need to add them ourselves.
Saunas purify our bodies. Sweat lodges are a combination of sauna and ceremony in which we purify our spirits as well. Saunas can be makeshift sweat lodges if we combine them with the ceremony of intention.
We purify our homes of negative energies. We can use cedar or sage to smudge them. We can sprinkle them with water and orange peel in a feng sui ritual. We can also sprinkle them with holy water. Catholic priests perform home-blessing rituals. We can burn salt for heavy-duty purification.
We can purify ourselves by smudging or taking ritual baths. Pets can also be smudged with burning sage. Dogs can be sprinkled but cats do not take well to sprinkling with water, holy or otherwise!
It is important to be purified after certain ordeals in life. Many cultures have rituals for purifying warriors returning home from war. This is an important emotional purification. We cannot expect people who fought in a war to just drop back into society like nothing has happened. They need a method of healing themselves from the experience.
After purification, it is important to remember that the past is now put to rest.