There is really no difference between matter, mind and Spirit. They are only different phases of experiencing the One.
Swami VivekanandaBooks suggest the inner light and the method of bringing that out, but we can only understand them when we have earned the knowledge ourselves. When the inner light has flashed for you, let the books go, and look only within. You have in you all and a thousand times more than is in all the books. Never lose faith in yourself, you can do anything in this universe. Never weaken, all power is yours.
Swami VivekanandaIt is good to love God for hope of reward, but it is better to love God for love's sake; and the prayer goes: O Lord, I do not want wealth nor children nor learning. If it be Thy will, I shall go from birth to birth. But grant me this, that I may love thee without the hope of reward 'love' unselfishly for love's sake.
Swami Vivekananda