After establishing a sense of safety in his conversation with Bathsheba, Adonijah asks for her permission to share a request. He makes it clear that he has a personal, secret matter to discuss, something that requires strict privacy so that no one else can hear [אברבנאל]. Only after she grants him permission does he step forward to reveal what is truly on his mind.
This secretive approach serves as a careful introduction to the bold statements he is about to make. He plans to present his case that the royal throne rightfully belonged to him, both because of his older age and because he had the support of the people. However, he frames this claim by expressing his acceptance that the kingship was ultimately given to his brother Solomon because it was the will of God [אברבנאל].