Bhakti is the one essential thing.
To be sure, God exists in all beings.
Who, then is a devotee? He whose mind dwells on God.
But this is not possible as long as one has egotism and vanity.
The water of God's grace cannot collect
on the high mound of egotism. It runs down.
One man may read the Bhagavata by the light of a lamp, and another may commit a forgery by that very light; but the lamp is unaffected. The sun sheds its light on the wicked as well as on the virtuous.
It's enough to have faith in one aspect of God. You have faith in God without form. That is very good. But never get into your head that your faith alone is true and every other is false. Know for certain that God without form is real and that God with form is also real. Then hold fast to whichever faith appeals to you.
The waves belong to the Ganges, not the Ganges to the waves. A man cannot realize God unless he gets rid of all such egotistic ideas as "I am such an important man" or "I am so and so". Level the mound of "I" to the ground by dissolving it with tears of devotion.
One should not think, 'My religion alone is the right path and other religions are false.' God can be realized by means of all paths. It is enough to have sincere yearning for God. Infinite are the paths and infinite are the opinions.
You speak of doing good to the world. Is the world such a small thing? And who are you, pray, to do good to the world? First realise God, see Him by means of spiritual discipline. If He imparts power you can do good to others; otherwise not.
Common men talk bagfuls of religion but do not practise even a grain of it. The wise man speaks a little, even though his whole life is religion expressed in action.