How does one achieve and maintain inner strength?

Question - Gurudev, how does one achieve and maintain inner strength?

Gurudev Sri Sri - By waking up to this knowledge. It should not be that just once a year you come, listen to some knowledge and go away. Make it part of your daily routine, so that it is maintained. Also, humility is important. Sometimes, people get so numb to knowledge. They think, 'I know it all.' One should not get into that arrogance, 'I know the knowledge, what is there to know'. The constant revival of knowledge, of the same points that you know, and reliving it is important. It is not a very tough or difficult task, and even if you lose the knowledge for a moment, it just comes back. Knowing that it comes back, you don't really lose it, it is there