Oliver O’Donovan explains that the word “tradition” refers to two things: (1) an action, and (2) a possession.
In the first sense it is the activity by which one shares in the community, receiving and contributing.
In the second sense it is the reserve of practices and communicative patterns received from the past—but only those which continue to command recognition, that is, which have been effectively communicated down to the present time.
He explains why tradition in this sense is so important:
The essential thing about tradition is that it creates social continuity.
It binds the communal action of the present moment to the communal actions of past moments.
He then distinguishes tradition from traditionalism:
What we often call “traditionalism,” the revival of lapsed tradition, is, properly speaking, a kind of innovation, making a new beginning out of an old model. This may or may not be sensible in any given instance, but it is not a tradition.
The claim of tradition is not the claim of the past over the present, but the claim of the present to that continuity with the past which enables common action to be conceived and executed.
The paradigm command of such tradition, O’Donovan argues, is “Honor your father and your mother, that your days may be long in the land which the Lord your God gives you” (Ex. 20:12). O’Donovan argues that it’s a mistake to think this passage is primarily concerned with the duties of children:
The duties of children are purely responsive to the duty of parents to be to their children what their parents were to them. This is a command addressed to adults, whose existence in the world is not self-posited but the fruit of an act of cultural transmission, which they have a duty to sustain. The act of transmission puts us all in the place of receiver and communicator at once. The household is envisaged as the primary unit of cultural transmission, the “father and the mother” as representing every existing social practice which it is important to carry on. Only so can community sustain itself within its environment, “the land which the Lord your God gives you.” No social survival in any land can be imagined without a stable cultural environment across generations. By tradition society identifies itself from one historical moment to the next, and so continues to act as itself. . . .
—Oliver O’Donovan, Common Objects of Love: Moral Reflection and the Shaping of Community (Grand Rapids, MI: Eerdmans, 2002), 33f.