In answering your first question I have in effect also answered the second. Grace is the diction of poetry. Devotion (bhakti) is itself poetry. But poetry is no improper or inferior or unnecessary thing. On the contrary it is badly needed. Science would tell us that water is a chemical compound of hydrogen and oxygen, but in the language of poetry water is a gift of God. Understanding such poetry is an essential element of life, while ignorance of the chemical composition of water does not matter in the least. It is perfectly logical to say that whatever happens is the fruit of action. But ‘Impenetrable is The Secret of Action’ (Gita IV, 17).We mortals are so constituted that we cannot know all the causative factors of even a very ordinary event. We are therefore perfectly right in saying that nothing happens except by the will and the grace of God. Again the body is a prison for the soul, who is like the air enclosed by a jar. The air in the jar is ineffective so long as it thinks itself to be different from the atmosphere. In the same way the soul imprisoned in the body will be unable to draw upon the Reservoir of Power that is God so long as she imagines herself to be a doer. Therefore to say that whatever happens happens by the will of God is to state a matter of fact, and such humility befits a seeker of truth. A lover of truth entertains only righteous wishes which are bound to be fulfilled. Our prayers bear fruit for the world to the extent that our soul is grounded in truth. The universe is not different from us, and we are not different from the universe. We are all members one of another, and influence one another by our actions. Actions here include thoughts, so that not a single thought is without its effect. Therefore we must cultivate the habit of always thinking good thoughts.