A pure Vaisnava is never self-centered, he only lives to give benefit and service to others.
“But Vaisnava is unhappy by seeing others suffering. Para-duḥkha-duḥkhī. That is the definition of Vaisnava.” (Swami Srila Prabhupada)
“Vāsudeva Datta told Caitanya Mahāprabhu, ‘My dear Lord, You incarnate just to deliver all conditioned souls. I now have one petition, which I wish You would accept. My Lord, You are certainly able to do whatever You like, and You are indeed merciful. If You so desire, You can very easily do whatever You want. My Lord, my heart breaks to see the sufferings of all the conditioned souls; therefore, I request You to transfer the karma of their sinful lives upon my head. My dear Lord, let me suffer perpetually in a hellish condition, accepting all the sinful reactions of all living entities. Please finish their diseased material life.’ ” (Caitanya Caritamrta Madhya-Lila 15.160-163)
The Christian brothers will say things like “Jesus Christ will take your sins and save you, but only if you follow him and this only applies to human beings’. This is conditional love. The Vedic follower Vasudeva Datta stated that he is prepared to accept the sins of all the living beings in the universe, regardless of whether they follow him or not. This is unconditional love. Thus, Vasudeva Datta is millions of times more loving and merciful than Jesus Christ.
Vasudeva Datta is an example of a pure Vaisnava.
“I am present in every living entity as the Supersoul. If someone neglects or disregards that Supersoul everywhere and engages himself in the worship of the Deity in the temple, that is simply imitation. (Lord Krishna, Shrimad-Bhagavatam 3.29-21)
If a person engages in Deity worship but treats others badly then this is considered low-level devotional service.
“One who worships the Deity of Godhead in the temples but does not know that the Supreme Lord, as Paramātmā, is situated in every living entity’s heart, must be in ignorance and is compared to one who offers oblations into ashes.” (Lord Krishna, Shrimad-Bhagavatam 3.29-22)
If one worships God in His Deity form and treats any living being badly, then his/her worship is simply useless and will yield no results. We must realize that God is present in every living being and thus giving pain to anyone is giving pain to God. We must not give pain to any living being.
“The devotee must know that in every living entity, however insignificant he may be, even in an ant, God is present, and therefore every living entity should be kindly treated and should not be subjected to any violence.” (Swami Srila Prabhupada, Shrimad-Bhagavatam purport 3.29.22)
“One who offers Me respect but is envious of the bodies of others and is therefore a separatist never attains peace of mind, because of his inimical behavior towards other living entities. My dear mother, even if he worships with proper rituals and paraphernalia, a person who is ignorant of My presence in all living entities never pleases Me by the worship of My Deities in the temple.” (Lord Krishna, Shrimad-Bhagavatam 3.29-23-24)
One must respect and treat every living being nicely, otherwise worshiping and performing rituals (pujas, chanting, pilgrimage, fasting etc..) will never please God.