The Path of Devotion is open to all

God is love. He is not bound by caste, creed or nationality. Everyone, whether man or woman, is entitled to enter the Path of Devotion. This Path is open to all. 

The following quotations are from the Ninth Discourse in the Gita:

A sinner, howsoever deeply fallen, if he turns to Me with undivided devotion, must indeed be counted a saint; for he has a settled resolve (to sin no more). The undivided devotion subdues both his passions and his evil deeds.

For soon he becomes righteous and wins everlasting peace; know ye for a certainty that My bhakta (devotee) never perishes.

For finding refuge in Me, even those born of sin and of low caste, shall reach the supreme goal.

In this way, the Bhagwat states that the Path of Devotion is for everybody. The lowliest of the low can become pure and clean by devotion to Him. The only requisites are faith and one-pointed devotion, which have the power to connect our soul with the Lord.

One who does not possess devotion and faith may be of a very high caste or even of a royal family, yet he is much lower than a person of a poor family and low caste who possesses devotion and faith. 

Narad says:

Devotees of the Lord are not distinguished by their birth, knowledge, beautiful appearance, high family status, wealth or even religious rites or rituals, because all true devotees are near and dear to the Lord. They are conscious of God inside as well as outside of themselves, and they are always happy in His company.

Another Rishi says:

Members of all castes and creeds, even if they are of a very low order, are entitled to tread the Path of Devotion. Such are the teachings of noble persons.

Amongst ancient orthodox Hindus the right of spiritual knowledge and action was not given to everybody. For instance, reading or reciting the Vedas was forbidden to members of the lowest caste. 

There are no restrictions barring anyone from the Path of Devotion.

Nobody will question you about your caste or your creed. He who devotes himself to the Lord is of the Lord.

The only aim on this Path is to have communion with the Lord and to achieve salvation. Ramanuj said in very emphatic language that worship of the Lord is the equal right of everyone, and that devotion frees the mind from all sectarian ties. 

Ramanand also spoke against caste and creed, saying:

Nobody should ask a person about his caste or creed, because whoever worships Him is of Him.

Chaitanya Dev also preached devotion without regard for caste or creed, and gave his teachings to everybody, whether man or woman.

If a person of low caste worships the Lord, he becomes high. Go and ask Bidur, a low caste person into whose hut the Lord Himself went. Oh my brothers, listen to the unwritten song of the Lord because by so doing the appetites of the mind and body will disappear.

Ravi Das, a poor cobbler, sang to the glory of the Lord. By so doing, this fallen man became noble, and all high-caste people touched his feet.

Nam Dev was devoted to the Lord. Although people called him a tailor, members of the highest caste raised him high, because from his lips came the Name of Hari (God) in pure devotion.

Of all devotees even if they have the tilak on their foreheads and have visited the sixty-eight places of pilgrimage, oh Nanak, only those are happy who are engaged, by His Grace, in the remembrance of the Lord.

Adi Granth