Faith is an important concept in Vajrayana or Esoteric Buddhism. It is especially important in the beginning, but it is an essential component in all stages of practice. When you begin to practice Buddhism, you may not understand the essence of the Dharma and thus cannot enter into true practice. As a result, you will not be able to experience any beneficial effects from your practice. You may not be able to acquire good fortune and wisdom or manifest supernormal powers immediately.
At this time, you must be careful not to commit the offense of giving rise to doubt about either your Vajra Master or the Dharma, since this will cause you to incur even more karmic obstacles and thus make it even more difficult to receive any benefits. Patience is very important at this stage in your practice. It is not uncommon for beginners to experience karmic retribution on this path as conditions from past activities occur. It is important that you fully understand the principles of karma and you not erroneously blame these consequences on the Dharma or your Master.
You must have faith in your master, the Dharma, and yourself to become accomplished. Since your master represents the buddhas, you must believe that your master can confer the special blessings of a buddha and correctly convey the Buddha’s teachings. You must also believe that these teachings—the Dharma—is the medicine you need to enable you to eliminate your obstacles and clear your obstructions to obtaining liberation. AND you must believe that you are capable of becoming a buddha. All three kinds of faith are essential on this path.
However, this is not a blind faith. You must also be certain that your master is an authentic Vajra Master who possesses the true Buddha-dharma. Since faith in your master is such an important part of this path, it is essential that you pick the right master.