By the time we die, we should ensure that we have done our part to improve the world. An individual should worship his homeland, traditions, and ancestors. He should remember to ‘water the roots’ every day, as well as do everything he can to make his descendants proud of their name, never forgetting him, or the clan. Such warriors are supported by ancestors from the other world. Remember the fundamental principal of life: everything around you is alive, surrounded by kami.
This great power pervades everything. Spirits guard and support those who are close to them and send negative energy to strangers. Make sure you remember your ancestors daily.
Celebrating Spring by Utagawa Kuniyoshi (woodblock print)
In Bushido one considers it essential to know the difference between the root and the branch, and to act accordingly. A man who has difficulty in discerning the root from the branch will likely have no understanding of duty, and it is difficult to call a man who does not understand duty a warrior. Knowing the difference between the root and the branch, one will consider his parents as the root of his body, and his body as the branch of their flesh and blood.
Read further in Samurai: Spirit of the Warrior
This an abstract from the chapter "The Cult of Ancestors" from Spirit of the Warrior by A. R. Berg