The purpose of incarnation is not merely to uphold the world order but to help the human beings to become perfected in their nature.

The steps required to be undertaken by beings in this regard are:
renouncing attachments to sense objects
becoming desireless
getting free from selfishness
realizing that he is constant, indestructible, eternal Self and that change is merely a quality of the body.

When an individual has reached this stage of self-development he becomes fearless and sees the Self everywhere and in such a state anger cannot arise in him. He is absorbed in Him and becomes fully devoted to Him. He thus takes absolute refuge in The Lord after getting purified with the fire of this knowledge.

The wisdom is referred to here as fire. Just as fire burns everything the wisdom burns down or completely removes all latent tendencies, impressions, cravings etc in an individual and thus makes him pure.

IS THE LORD PARTIAL TOWARDS SOME?

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Bahavah, many; vita-raga-bhaya-krodhah, who were devoid of attachment, fear and anger; manmayah, who were absorbed in Me, who were knowers of Brahman, who were seers of (their) identity with God; mam upasrithah, who had taken refuge only in Me, the supreme God, i. e. who were steadfast in Knowledge alone; and were putah, purified, who had become supremely sanctified; jnana-tapasa, by the austerity of Knowledge-Knowledge itself, about the supreme Reality, being the austerity; becoming sanctified by that austerity of Knowledge-; agatah, have attained; madbhavam, My state, Goodhood, Liberation.

The particular mention of ‘the austerity of Knowledge’ is to indicate that steadfastness in Knowledge does not depend on any other austerity.

‘In that case, You have love and aversion, because of which You grant the state of identity with Yourself only to a few but not to others?’

The answer is: