Men have their virtues and their vices, their heroisms and their perversities; men are neither wholly good nor wholly bad, but possess and practice all that there is of good and bad here below. Such is the general rule. Temperament, education, the accidents of life, are modifying factors. Outside of this, everything is ordered arrangement, everything is chance. Such has been my rule of expectation and it has usually brought me success.
If you desire to be pure, have firm faith, and slowly go on with your devotional practices without wasting your energy in useless scriptural discussions and arguments. Your little brain will otherwise be muddled.
If you listen to the Dhamma teachings but don't practice you're like a ladle in a soup pot. The ladle is in the soup pot every day, but it doesn't know the taste of the soup. You must reflect and meditate.