Is this acceptance or rejection something you do?
if you believe you are saved by faith plus something else you do - regardless of what that something else is - then you are NOT placing your trust in Jesus Christ as your savior
When someone who loves you gives you a gift, you can accept the gift or turn it down, either way "a gift" by virtue of the word implied is not something earned, not something for which you "do" anything. If you receive it, it is yours, if you reject it, you do not have it. I don't know any way to explain it in simpler terms.