My only defense? on the contrary Aineo, you haven't proved anything but gone in circles with unsubstantiated arguments which have been rebutted. But in your attempt to deny this, you resort to personal interpretation and opinion.
Do you know the meaning of "Until the redemption of the purchased possession"? You can use the legality of the covenant in an attempt to insert it into the context of that passage, that phrase "Until the redemption of the purchased possession" is translated as "Until God glorifies and perfects the believer[the purchased possession], whom He has bought by Christ's blood". To state that the believer can choose to reject the contract is ridiculous, since God is working within the believer to both Glorify and perfect him/her. You can go back and forth with your statement of "genuine believers" cannot become apostate, which is simply using the usual OSAS defense "they were never saved in the first place". However it is a legitimate question, and unless you can indubitably prove that the apostates in the passage formentioned were indeed saved, your rebuttals are ineffective. BTW, if you consider calling someone "ignorant" name calling, then try considering the vocabulary used in your posts found on this forum.