Whenever God descends on this earth, there are many purposes, but mainly, our scriptures say there are three purposes of the descension of God,
paritrāṇāya sādhūnām (for the protection of the devotees),
vināśhāya cha duṣhkṛitām (for the destruction of the wicked),
sansthāpanāya dharmasya (for the establishment of dharm).
First is to protect and help the devotees, the good people. (Then) vināśhāya cha duṣhkṛitām, to kill the demons and dharmasaṁsthāpanārthāya, for the establishment of righteousness.
These are the main purposes of the avatar (Divine descension) of God, but there are many hidden purposes as well in all the avatars. When Lord Krishna descended 5000 years ago on this earth, at that time also, He did all these works. But the main purpose was to bestow Divine love-bliss to the deserving souls, and He was establishing this ideal also. Don’t think that God is only formless.
There were many gyānis (followers of the path of knowledge) at that time. And this kind of a concept was very common that God is nirākār (formless). Because He is omnipresent, He pervades each and every particle of the world. That’s why He is nirākār and He cannot descend with any form on this earth. But it was wrong.
द्वे वाव ब्रह्मणो रूपे मूर्तं चैवामूर्तं च …
Dve vāva brahmaṇo rūpe mūrtaṃ chaivāmūrtaṃ cha …- Bṛihadāraṇyaka Upaniṣhad 2.3.1
There are two forms of God, mūrt (with form) and amūrt (without form), which means sākār and nirākār - nirākār, formless and sākār, with a form, with a personal form.
So there are two forms of God.
