SB 11.5.50

bhū-bhārāsura-rājanya-
 hantave guptaye satām
avatīrṇasya nirvṛtyai
 yaśo loke vitanyate
Synonyms: 
bhū-bhāra — who were the burden of the earth; asura — demons; rājanya — members of the kingly order; hantave — in order to kill; guptaye — for the protection; satām — of the saintly devotees; avatīrṇasya — of Him who has descended; nirvṛtyai — also for awarding liberation; yaśaḥ — the fame; loke — throughout the world; vitanyate — has become spread.
Translation: 
The Supreme Personality of Godhead descended to kill the demoniac kings who were the burden of the earth and to protect the saintly devotees. However, both the demons and the devotees are awarded liberation by the Lord’s mercy. Thus, His transcendental fame has spread throughout the universe.
Purport: 

A doubt may arise as to how the Supreme Personality of Godhead descends to this material world. And since He is the omnipotent creator of millions of universes, why do the devotees glorify as wonderful the Lord’s activities such as His killing a witch named Pūtanā by sucking out her life through her breast? Although such activities are certainly beyond the scope of ordinary human beings, why should they be considered wonderful when executed by the omnipotent Personality of Godhead? The answer is given in this verse by the word nirvṛtyai. The Lord killed the demons not because He was envious of them, but in order to give them spiritual liberation. Thus the causeless mercy of the Personality of Godhead in liberating both the devotees and the demons by His inconceivable pastimes clearly distinguishes the Lord from any other living entity, either man or demigod. It is stated, mukti-pradātā sarveṣāṁ viṣṇur eva na saṁśayaḥ: only Viṣṇu can give liberation beyond birth and death. Śrīla Viśvanātha Cakravartī Ṭhākura has pointed out that generally the demons are awarded impersonal liberation in the Brahman effulgence, whereas the devotees are given the superior benediction of love of Godhead in the spiritual planets. Thus, the Lord exhibits His causeless mercy toward all classes of living entities, and His fame is spread throughout the universe. Because Kṛṣṇa is transcendental, His fame is not different from His personal incarnation, so as the Lord’s fame expands, the entire universe is gradually liberated. These are some of the unique characteristics of the Supreme Personality of Godhead.