Narasimha Chaturdashi is the divine appearance day of Narasimha Deva, Lord Krishna’s man-lion incarnation, who removes all obstacles on the path of devotional service out of His great compassion.
Srila Prabhupada writes (Bhagavatam 7.8.51, purport):
The Supreme Personality of Godhead in His transcendental form of Lord Narasimha Deva is always ready to kill the demons that always create disturbances in the minds of honest devotees. To spread the Krishna consciousness movement, devotees have to face many dangers and impediments all over the world, but a faithful servant who preaches with great devotion to the Lord must know that Lord Nrisimhadeva is always his protector.
At ISKCON Sri Narasimha Giridhari Mandir, Narasimha Chaturdasi is very special as devotees assemble in great numbers and with great joy to observe this festival and chant the glories of Lord Narasimha Deva. The Srimad-Bhagavatam class focuses on various aspects of Lord Narasimha Deva’s pastimes, usually given by two or three devotees.
The celebrations begin at the dusk, with an elaborate abhisheka for the mula Deity of Sri Lakshmi Narasimha Deva. The Lord is also offered a new dress and jewelry. During the abhisheka panchagavya, panchamrita, sacred water, herbal water, sandal, water, fruit juices, and water mixed with turmeric are poured on the Lord for His pleasure. A grand arati is performed. 108 kalashas of sacred water sanctified by specific mantras are poured on the Lord as the devotees chant the Vedic Purusha Sukta Mantra. The Lord receives an offering of 56 varieties of bhoga items. The festival then culminates with shayana-arati. The deities of Nava Narasimha also bestow Their mercy upon all the devotees by giving Their darshan.