Lord Śrī Kṛṣṇa appeared on this planet out of compassion for fallen souls; Lord Buddha appeared out of compassion for the poor animals who were being killed by the demons; Lord Nṛsiṁhadeva appeared out of compassion for Prahlāda Mahārāja. The conclusion is that the Lord is so compassionate upon the fallen souls within this material world that He comes Himself or sends His devotees and His servants to fulfill His desire to have all the fallen souls come back home, back to Godhead. Thus Lord Śrī Kṛṣṇa instructed Bhagavad-gītā to Arjuna for the benefit of the entire human society. Intelligent men should therefore seriously consider this Kṛṣṇa consciousness movement and fully utilize the instructions of Bhagavad-gītā as preached without adulteration by His pure devotees.
(Srimad Bhagavatam--------4:21:42-------purport).

Therefore, as Kṛṣṇa is always compassionate to the fallen souls, His servants, the devotees of Lord Kṛṣṇa, are also interested in educating the entire populace in Kṛṣṇa consciousness. The mistake of materialistic life is understood by devotees, and therefore they smile upon it, considering it insignificant. Out of compassion, however, such devotees preach the gospel of Bhagavad-gītā all over the world.
(Srimad Bhagavatam--------7:5:55-------purport).

Out of His causeless mercy and compassion, Kṛṣṇa has compiled various Vedic literatures in His incarnation as Vyāsadeva. Vyāsadeva is a śaktyāveśa-avatāra of Lord Kṛṣṇa. He has very kindly presented these literatures to awaken the conditioned soul to his senses. Unfortunately, at the present moment the conditioned souls are guided by demons who do not care to read the Vedic literatures. Although there is an immense treasure-house of knowledge, people are engaged in reading useless literature that will give them no information on how to get out of the clutches of māyā.
(Sri Caitanya Caritamrta-------2:20:122-------purport).

When Prahlāda Mahārāja was offered benediction by Nṛsiṁha-deva, due to his great devotion and tolerance he refused to accept any benediction from the Lord, thinking that such acceptance was not befitting a sincere devotee. The rendering of service to the Supreme Personality of Godhead in expectation of a good reward is deprecated by Prahlāda Mahārāja as mercantile business. Because Prahlāda Mahārāja was a Vaiṣṇava, he did not ask a benediction for his personal self but was very affectionate toward his father. Although his father tortured him and would have killed him had he himself not been killed by the Supreme Personality of Godhead, Prahlāda Mahārāja begged pardon for him from the Lord. This favor was immediately granted by the Lord, and Hiraṇyakaśipu was delivered from the darkest region of hellish life, and he returned back home, back to Godhead, by the grace of his son. Prahlāda Mahārāja is the topmost example of a Vaiṣṇava, who is always compassionate toward sinful persons suffering a hellish life within this material world. Kṛṣṇa is therefore known as para-duḥkha-duḥkhī kṛpāmbudhiḥ, or one who is compassionate toward others' suffering and who is an ocean of mercy. Like Prahlāda Mahārāja, all pure devotees of the Lord come to this material world with full compassion to deliver the sinful. They undergo all kinds of tribulations, suffering them with tolerance, because that is another qualification of a Vaiṣṇava, who tries to deliver all sinful persons from the hellish conditions of material existence. Vaiṣṇavas are therefore offered the following prayer:
vāñchā-kalpatarubhyaś ca
kṛpā-sindhubhya eva ca
patitānāṁ pāvanebhyo
vaiṣṇavebhyo namo namaḥ
(I offer my respectful obeisances unto all the Vaiṣṇava devotees of the Lord. They can fulfill the desires of everyone, just like desire trees, and they are full of compassion for the fallen souls.)

The chief concern of a Vaiṣṇava is to deliver the fallen souls.

(Srimad Bhagavatam--------4:21:47-------purport).

Kṛṣṇa took compassion upon Brahmā because of his inability to see how Kṛṣṇa was displaying the forms of Viṣṇu and transforming Himself into calves and cowherd boys, and thus, while fully manifesting the Viṣṇu expansions, He suddenly pulled His curtain of yogamāyā over the scene. In the Bhagavad-gītā it is said that the Supreme Personality of Godhead is not visible due to the curtain spread by yogamāyā. That which covers the reality is mahā-māyā, or the external energy, which does not allow a conditioned soul to understand the Supreme Personality of Godhead beyond the cosmic manifestation. But the energy which partially manifests the Supreme Personality of Godhead and partially does not allow one to see is called yogamāyā. Brahmā is not an ordinary conditioned soul. He is far, far superior to all the other demigods, and yet he could not comprehend the display of the Supreme Personality of Godhead; therefore Kṛṣṇa willingly stopped manifesting any further potency. The conditioned soul not only becomes bewildered but is completely unable to understand. The curtain of yogamāyā was drawn so that Brahmā would not become more and more perplexed.

(Krsna Book).