A tenet is a principle held as being true, especially by an organization or a group of people.
A tenant is (1) someone who pays rent to occupy property; (2) a dweller in a place; and, (3) in law, one who holds or possesses lands, tenements, or property by any kind of title.
Examples
Tenet
He said it was unethical and goes against the tenets of Islam. [Arab News (dead link)]
By destroying this very tenet of capitalism – that the losers actually lose so that new ideas, people, companies can become winners – they have now crippled our economy and kept millions out of work. [TPM (dead link)]
Tenant
A group of Queens tenants left homeless by a fire two weeks ago fear many of their belongings were looted or just tossed out like garbage. [NY Daily News]
Supporters of tenants’ rights are disappointed that an overhaul of tenancy laws did not result in the demise of agency letting fees. [Radio New Zealand]