Faith and bhakti are different. Faith implies that one believes that there is some good purpose for doing something. That is, though there may be lack of personal experience, one has sufficient faith to accept that the experience does exist. Without faith we would be nothing in life. Without faith we would not practise asanas, pranayama, meditative techniques or any other yogic practices. If we did not have faith that there is a good reason behind them, then we would never practise them. When practice is translated into experience, then faith drops away. It becomes superfluous. Faith is associated with the instructions of the guru. Without faith one would not follow his instructions. Without faith a guru-disciple relationship cannot exist.
Faith leads to the experience of bhakti. This is not blind faith, but acceptance that certain actions and efforts need to be done in order to tread the path to expanded awareness, to that which is presently beyond comprehension.
Faith implies that your practices of bhakti yoga and other forms of yoga will lead you somewhere, that they will not lead you into the depths of ignorance. There has to be faith that the path of bhakti yoga does lead to higher awareness and bliss. You have to have faith in the efficiency of the sadhana. Without this faith you would never do anything. The darshan I meeting) with a great sage or your guru will intensify faith, for you will see a living example of a person who has travelled the path that you are presently travelling. This is a great source, inspiration and intensifier of faith.