Lord Caitanya did not invent a system of religion, as people sometimes assume. Religious systems are meant to show the existence of God, who is then generally approached as the cosmic order-supplier. But Lord Śrī Caitanya Mahāprabhu's transcendental mission is to distribute love of Godhead to everyone. Anyone who accepts God as the Supreme can take to the process of chanting Hare Kṛṣṇa and become a lover of God. Therefore Lord Caitanya is the most magnanimous. This munificent broadcasting of devotional service is possible only for Kṛṣṇa Himself. Therefore Lord Caitanya is Kṛṣṇa.
(Sri Caitanya Caritamrta----1:4:41----purport).

Śrī Caitanya Mahāprabhu's mission is thus described by Narottama dāsa Ṭhākura: patita-pāvana-hetu tava avatāra/ mo-sama patita prabhu nā pāibe āra. If Śrī Caitanya Mahāprabhu descended to reclaim sinners, then one who is the most sinful and lowborn is the first candidate for the Lord's consideration.
(Sri Caitanya Caritamrta----2:11:46----purport).

Śrī Caitanya Mahāprabhu's special mission is the deliverance of all fallen souls in Kali-yuga. Devotees of Kṛṣṇa must persistently seek the favor and mercy of Śrī Caitanya Mahāprabhu to become fit to return home, back to Godhead.
(Sri Caitanya Caritamrta----2:14:16----purport).

The mission of Śrī Caitanya Mahāprabhu is to spread the only medicine effective in this fallen Age of Kali—the chanting of the Hare Kṛṣṇa mahā-mantra. Following the orders of His mother, Śrī Caitanya Mahāprabhu was residing at Jagannātha Purī, and the devotees were coming to see Him. However, the Lord felt that this message must be spread very elaborately in Bengal, and in His absence there was not a second person capable of doing it.
(Sri Caitanya Caritamrta----2:16:64----purport).

A Vaiṣṇava is especially interested in para-upakāra, doing good to others. Prahlāda Mahārāja was also interested in this. He did not want to be delivered alone; rather, he wanted to deliver all fallen souls, who are bereft of knowledge of bhakti and who misuse their intelligence for the temporary benefit of the material body. Śrī Caitanya Mahāprabhu also wanted His mission spread all over the world.
(Sri Caitanya Caritamrta----2:25:264----purport).

Lord Caitanya's mission is to deliver the fallen souls of this age. In this Age of Kali, practically cent percent of the population is fallen. Śrī Caitanya Mahāprabhu certainly delivered many fallen souls, but His disciples mainly came from the upper classes. For example, He delivered Śrīla Rūpa Gosvāmī, Sanātana Gosvāmī, Sārvabhauma Bhaṭṭācārya and many others who were socially elevated but fallen from the spiritual point of view.
(Sri Caitanya Caritamrta----2:25:271----purport).

Those who are following in the footsteps of Śrī Caitanya Mahāprabhu should take the Lord's mission most seriously. In this Age of Kali, people are gradually becoming less than animals. Nevertheless, although they are eating the flesh of cows and are envious of brahminical culture, Śrī Caitanya Mahāprabhu is considering how to deliver them from this horrible condition of life.
(Sri Caitanya Caritamrta----3:3:51----purport).

The point is that one must take up a particular path and stick to it, obeying all the rules and regulations necessary for success in spiritual life. It was Lord Caitanya's mission that He teach the path of Kṛṣṇa consciousness to all men and thereby enable them to partake of the immortality of spiritual life.
(Teachings of Lord Caitanya).