It only work when you say it, if you don’t say it, it doesn’t work.
The legal aspect has to do with acknowledging and acting accordingly. Because it is about being informed of what belongs to you, who you are, what have been done for you in Christ and what your inheritance is.
But the vital aspect of salvation is only activated when you confess it. In other word, you got to say it, you got to affirm it.
Affirmation is the major part of Christianity, you never get into real Christianity without affirmation of the word and truth.
If you don’t affirm it, it never works. You will only be left with religion and religion is a burden. It doesn’t bless anyone.