Espouse (verb)

1. To support or advocate (an idea or cause).
2. To take up or adopt (a belief or attitude).
3. To take as one's own (an idea or principle).
4. To marry (someone).

Origin:

Middle english (formerly also as espousen): from old french espouser, from latin sponsare, from spondere "betroth", from spondere "promise".

Examples:

1. He espoused the cause of civil rights.
2. The government espoused the idea of free trade.
3. He espoused a new religion.
4. She espoused a vegan lifestyle.
5. They espoused each other in front of the altar.