Heredity was passed through the mother's side, so the children belonged to their mother's crest, but the father's crest had duties to those children. None could marry within their own major crest. The women usually went to live with their husbands, but their sons would return to her village to be educated by her brother.
The Tsimshian had both a Halait season and a Potlatch season. Halait means dance, power, spirit and sacredness. The major halait ceremony is the Naxnox (which loosely means spirit). There were the names of spirits which were also the names of houses, so naxnox names were also inherited through the mother. Adults were given Naxnox names, their previous names being known as their baby names. Naxnox names were dramatizations, usually of anti-social qualities like Proud, Slave, and Nods-All-The-Time. Those with a Naxnox name got in front of everyone and dramatized his or her name and the audience would try to guess the name. The audience usually knew, but it was a fun affair in which those of less rank could be more loose with the high-ranked. It was a time to laugh. Rank and spiritual power usually went hand-in-hand. Connected to the spiritual ceremonies were the Gitsonck. The Gitsonck were a secret group of artists that helped dramatize miracles at Halait ceremonies. They were separate from the crest artists, who were openly known. The miracles were enteraining, but also serious affairs. Gitsonck whose miracles did not were severely punished, sometimes killed - if they did not kill themselves first.
The Potlatch with the Tsimshian, as with the other NW Coast Nations, is a spiritual, economic, social, legal and educational institution. The host provides a large feast, there is singing, dancing, story-telling and gift-giving. Gift-giving occurred in order of rank and the value of gifts corresponded to the rank of the person it was for. The leaders were also responsible for keeping a surplus of food and necessities to redistribute to those in need. So the system was not purely hierarchical for the sake of status but also a rational way of assigning responsibility to a group of people for those having a hard time. That the potlatch was a legal and educational system is seen in that it was the place where ownership of any properties was told in the family histories and (hopefully) verified after the story-telling.
The Tsimshian believe that spirits exist here and now and need to be respected. The spirits are everywhere at any moment, and they will cooperate or not depending on whether or not they are respected.