Education and training of children

Among the greatest of all services that can possibly be rendered by man to Almighty God is the education and training of children..." 

‘Abdu’l-Baha  (‘Selections from the Writings of ‘Abdu’l-Baha’; included in Ruhi Book 3)

One's vision

O Man of Two Visions! Close one eye and open the other. Close one to the world and all that is therein, and open the other to the hallowed beauty of the Beloved. 
- Baha'u'llah  (‘The Hidden Words of Baha’u’llah’; included in Ruhi Book 2)

The effect of "pure and goodly deeds"

The betterment of the world can be accomplished through pure and goodly deeds, through commendable and seemly conduct. 
- Baha’u’llah  (quoted by Shoghi Effendi in ‘The Advent of Divine Justice’; included in Ruhi Book 1)