Worshipping Eeshvara vs deities

In Advaita Vedanta, though Eeshvara (Brahman) is the creator of Maya, he doesn't do anything else within it.

The only understanding one gains from knowing Eeshvara is that he is all-knowing, and is your true self, and is the one who created the Maya you're experiencing - and therefore you have a guarantee that everything is going to turn out right eventually.

However, as the fate unfolds, the ones who help you are the deities. That is, within Maya, you are bound to cause and effect by your own choice, and your goal is to navigate the maze and attain liberation. But in that process, when you're overcome by darkness, you need the help of deities to be the light that dispels it.

Now Bhagavad Geeta points out the metaphysics, guides you to understanding it, and then also advises you to have Bhakti to your own Swaroopa as Eeshvara as part of Bhakti Yoga. And it doesn't directly recommend worshipping multiple deities. But the Swaroopa of any entity at all is Eeshvara. Therefore, the Swaroopa of any Eeshvara Swaroopa deity you envision is Eeshvara itself. There is no difference at all in terms of the being, but Eeshvara is Brahman itself, and Brahman is not actively participating in Maya besides creating it and letting it unfold. It is the immanent aspect of Eeshvara that interferes in the world.

One may wonder, if you know that Eeshvara is one, and that Maya is one, then why should one not focus on realizing that directly? It is because the nature of Maya is such that the truth is evasive. So while you are being corrected, you need help. You can indeed do this, and this is called the path of knowledge, or Jnana Yoga. But in a world with distractions, that is difficult and you'll need aid, and that's the role of devotion.

Likewise, as for worshipping multiple deities instead of one, our philosophy simply allows for that. But it's not like that we must separatelyy satisfy all deities in order to get their rewards. No. An Eeshvara Swaroopa Moorti is self-satisfied, and their worship is only to fill your mind with thoughts of them, and to be like them.

Now the point is that you must worship Eeshvara Swaroopa deities. In other words, those deities, or Moortis (forms) will have to be Kaarana Swaroopa Moortis. If instead, you worship a Karya Swaroopa Moorti, what you will get is a reward in the world, which will be subject to Karma. This is the same as how to attain any success in the world, you need to out in some effort. And if what you attain is without any real effort then it's a shortcut, and they always backfire. So for true liberation, the right path is to worship Eeshvara Swaroopa Moortis.

More specifically, any Sadhaka must perform 4 activities. They are (1) Karma Yoga, (2) Eeshvara Dhyaana, (3) Sat Gunatvam and (4) Vedanta Vichara / Nididhyaasana. (I found these in a mailing list, but the description is pretty accurate. One need not see it as four separate facets, because all of them are connected, and doing a few also draws you into the others. But anyways, this is it.)

Now in addition to all this, Eeshvara can also, as part of the plan, take birth as an Avatara at any time he deems in necessary, since Maya is his creation. So it is not necessary for any being to peer into the future and conclude that there is no safe future, and it is only necessary for beings to understand that the existence of the world implies an Eeshvara. This is stated in Bhagavad Geeta, Chapter 4: Jnana Karma Sannyasa Yoga, Verse 7:

yadā yadā hi dharmasya, glānir bhavati bhārata;

abhyutthānam adharmasya, tadātmānaṁ sṛijāmyaham.

I must note that this, and everything else here, is possible because Eeshvara is not only transcendent, but also immanent. This is a condition that's not possible in Islam. Christianity does believe that God is both transcendent and immanent, but there is a strong divide between divine nature and human nature. However, here, the true nature of the Creation is the same as that of the Creation, which is Brahman.

In this way, this also avoids the atheist argument of how an all-perfect all-benovelent being could've created a world of suffering. Here the being is all-perfect, omniscient and omnipresent, but it is not omnibenevolent, because there is no real duality. But rather, it tries creates a world specifically to experience life in bondage and find its way to liberation. One can't call that omnibenevolence. It is just a play, or Leela. No one blames a director for making characters suffer. And in this case, unlike movies which end abruptly, all charactrers eventually attain liberation. Kind of like movies like Fast and Furious with twists where all characters come back to life.