“Good faith seeks to flee the inner disintegration of my being in the
direction of the in-itself which it should be and is not. Bad faith
seeks to flee the in-itself by means of the inner disintegration of
my being. But it denies that it is itself in bad faith. Bad faith seeks
by means of “not-being-what-one-is” to escape-from the in-itself
which I am not in the mode of being what one is not. It denies
itself as bad faith and aims at the in-itself which I am not in the
mode of “not-being-what-one-is-not.” If bad faith is possible, it
is because it is an immediate, permanent threat to every project of
the human being; it is because consciousness conceals in its being a
permanent risk of bad faith. The origin of this risk is the fact that
the nature of human consciousness simultaneously is to be what it
is not and not to be what it is.”
Here Sartre contrasts both “good-faith” and “bad faith”. According to Sartre there is a tension between GF and BF which is similar to what he means by “Being” and “Nothingness” (the title of the book) or to put it another way facticity and liberty. Also, the “in-itself” refers to what man ought to be or facticity.
According to Sartre the tension between BF and GF becomes unbearable with the realization of BF that man has the liberty to self-authenticate or be what he wants. In such a case he will go so far as to lie to himself about GF in order to adopt the liberty in BF. Such is the reason Sartre says “… the nature of human consciousness simultaneously is to be what it is not and not to be what it is.
Such an attitude is what I referred to earlier as self-deception.