Srimad Bhagavatam has answers to all your doubts.
SB 12.3.45: In the Kali-yuga, objects, places and even individual
personalities are all polluted. The almighty Personality of Godhead,
however, can remove all such contamination from the life of one who
fixes the Lord within his mind.
SB 12.3.46: If a person hears about, glorifies, meditates upon,
worships or simply offers great respect to the Supreme Lord, who is
situated within the heart, the Lord will remove from his mind the
contamination accumulated during many thousands of lifetimes.
SB 12.3.47: Just as fire applied to gold removes any discoloration
caused by traces of other metals, Lord Viṣṇu within the heart purifies
the minds of the yogīs.
SB 12.3.48: By one's engaging in the processes of demigod worship,
austerities, breath control, compassion, bathing in holy places,
strict vows, charity and chanting of various mantras, one's mind
cannot attain the same absolute purification as that achieved when the
unlimited Personality of Godhead appears within one's heart.
SB 12.3.49: Therefore, O King, endeavor with all your might to fix the
Supreme Lord Keśava within your heart. Maintain this concentration
upon the Lord, and at the time of death you will certainly attain the
SB 12.3.50: My dear King, the Personality of Godhead is the ultimate
controller. He is the Supreme Soul and the supreme shelter of all
beings. When meditated upon by those about to die, He reveals to them
their own eternal spiritual identity.
SB 12.3.51: My dear King, although Kali-yuga is an ocean of faults,
there is still one good quality about this age: Simply by doing Hari
Kirtan, one can become free from material bondage and be promoted to
the transcendental kingdom.
SB 12.3.52: Whatever result was obtained in Satya-yuga by meditating
on Viṣṇu, in Tretā-yuga by performing sacrifices, and in Dvāpara-yuga
by serving the Lord's lotus feet can be obtained in Kali-yuga simply
by doing Hari Kirtan.
Note: I have copied this from an ISKCON site, so I've edited their version of getting moksha from "Hare Krishna mahamantra" to "doing Hari kirtan", because the original Sanskrit mentions the general term "hari-kīrtanāt", which is essentially any form of kirtan, not only the ISKCON way.
Also this is a passage from The Gospel of Sri Ramakrishna:
Vijay: "But those who discriminate according to the Vedanta philosophy
also realize Him in the end, don't they?"
Sri Ramakrishna: "Yes,
one may reach Him by following the path of discrimination too: that is
called jnana yoga. But it is an extremely difficult path. I have told
you already of the seven planes of consciousness. On reaching the
seventh plane the mind goes into samadhi. If a man acquires the firm
knowledge that Brahman alone is real and the world illusory, then his
mind merges in samadhi. But in the Kaliyuga the life of a man depends
entirely on food. How can he have the consciousness that Brahman alone
is real and the world illusory? In the Kaliyuga it is difficult to
have the feeling, 'I am not the body, I am not the mind, I am not the
twenty-four cosmic principles; I am beyond pleasure and pain, I am
above disease and grief, old age and death.' However you may reason
and argue, the feeling that the body is identical with the soul will
somehow crop up from an unexpected quarter. You may cut a peepal-tree
to the ground and think it is dead to its very root, but the next
morning you will find a new sprout shooting up from the dead stump.
One cannot get rid of this identification with the body; therefore the
path of bhakti is best for the people of the Kaliyuga. It is an
"But it isn't any and every kind of bhakti that enables one to realize
God. One cannot realize God without prema-bhakti. Another name for
prema-bhakti is raga-bhakti. (Supreme love, which makes one attached
only to God.) God cannot be realized without love and longing. Unless
one has learnt to love God, one cannot realize Him.
kind of bhakti, known as vaidhi-bhakti, according to which one must
repeat the name of God a fixed number of times, fast, make
pilgrimages, worship God with prescribed offerings, make so many
sacrifices, and so forth and so on. By continuing such practices a
long time one gradually acquires raga-bhakti. God cannot be realized
until one has raga-bhakti. One must love God. In order to realize God
one must be completely free from worldliness and direct all of one's
mind to Him."