If our resolve is sufficiently strong, our desire is exclusive and faith complete, we will attain success. In a dark room kept closed for years, the darkness disappears the moment the sun's rays enter. The dark room does not argue that as it occupied the room for such a length of time. The moment light enters, darkness is dead and gone.
The moment explosiveness and strength of resolve, desire and faith are attained, there is revelation of the divine light. That very instant, the darkness coming down from eternity disappears. Hence exert yourself with fullness of faith in your heart.