Abraham didn't try to fulfill the promise himself; he waited for God to do it.
Naho Abrahamu o vha a sa ḓivhi uri eneo mafhulufhedziso a Mudzimu a ḓo ḓadzea lini, o bvela phanḓa a tshi fulufhela nga ho khwaṱhaho uri a ḓo ḓadzea.