How can one achieve faith and know that they are among the guided, given the presence of whispers that raise doubts about the strength of faith or the benefit of adhering to religion?

A servant's feeling of shortcoming and their displeasure with it is a sign of goodness and faith, and an indication of the perfection of faith, unlike the hypocrite who does not care. Attributing this to a weakness in faith is a valid point, but one should not exaggerate it so that it does not lead to despair and loss of self-confidence. Satan plays a role in instilling these whispers to make obedience difficult and disliked, and this contradicts the fact that religion is ease and not hardship.