the mind > language > speech > agreement > promise > promise or vow [verb (transitive)] > pledge or undertake to give or do > pledge oneself to a cause (2)
espouse1538
transitive. figurative. To pledge, commit, engage (a person) (to something, or (occasionally) †to do something). In later use only reflexive (cf…
betroth1658
transferred. To pledge or engage oneself to, to espouse (a cause). Obsolete.