Wikipedia.
Brahmo Samaj is the societal component of the Brahmo movement which is also called the Adi Dharm.
It was one of the most influential religious movements responsible for the making of modern India.
It was conceived at Kolkata in 1830 by Debendranath Tagore and Ram Mohan Roy as reformation of the prevailing Brahmanism of the time and began the Bengal Renaissance of the 19th century pioneering all religious, social and educational advances of the Hindu community in the 19th century.
The Brahmo Samaj literally denotes communities of men who worship Brahman.
In practice, a Brahmo Samaj is an assembly of all sorts and descriptions of people without distinction, meeting publicly for the sober, orderly, religious and devout adoration of "the (nameless) unsearchable Eternal, Immutable Being who is the Author and Preserver of the Universe."
On 20 August, 1828 the first assembly of the Brahmo Sabha (progenitor of the Brahmo Samaj) was held at the North Calcutta house of Feringhee Kamal Bose. This day is celebrated by Brahmos as Bhadrotsab ("Bhadro celebration"). These meetings were open to all Brahmins and there was no formal organisation or theology as such.
On 8 January, 1830 influential progressive members of the closely related Kulin Brahmin clan of Tagore (Thakur) and Roy (Vandopadhyaya) executed the Trust deed of Brahmo Sabha for the first Adi Brahmo Samaj (place of worship) on Chitpore Road (now Rabindra Sarani), Kolkata, India with Ram Chandra Vidyabagish as first resident superintendent.
On 23 January, 1830 the Adi Brahmo premises was publicly inaugurated (with about 500 Brahmins and 1 British present). This day is celebrated by Brahmos as Maghotsab (Magh celebration).
In November 1830 Rammohun Roy left for the United Kingdom.
The affairs of Brahmo Sabha were effectively managed by Trustees Dwarkanath Tagore and Pandit Ram Chandra Vidyabagish, with Dwarkanath instructing his diwan to manage affairs.
By the time of Rammohun's death in 1833 near Bristol (UK), attendance at the Sabha dwindled.
On 6 October, 1839 Debendranath Tagore, son of Dwarkanath Tagore, established Tattvaranjini Sabha which was shortly thereafter renamed the Tattwabodhini (Truth-Seekers) Sabha. Initially confined to immediate members of the Tagore family, in 2 years it mustered over 500 members.
In 1843, Debendranath Tagore and 20 others were formally invited into the Trust of Brahmo Sabha.
In 1861 the Brahmo Samaj opened its doors to non-Bengalis around India.
It has more than 20,000 members today.
Brahmos believe in social reform, including abolition of the caste system and dowry system, emancipation of women and improving the educational system.
Brahmo Samajists have no faith in any scripture as literal authority.
Brahmo Samajists have no faith in Avatars.
Brahmo Samajists denounce polytheism and idol-worship.
Brahmo Samajists are against caste restrictions.
Brahmo Samajists make faith in the doctrines of Karma and Rebirth optional.
On God: There is always Infinite Singularity – immanent and transcendent Singular Author and Preserver of Existence – He who is manifest everywhere and in everything, in the fire and in the water, in the smallest plant to the mightiest oak.
On Being: Being is created from Singularity. Being is renewed to Singularity. Being exists to be one (again) with Loving Singularity.
On Intelligent Existence: Righteous actions alone rule Existence against Chaos. Knowledge of pure Conscience (light within) is the One (Supreme) ruler of Existence with no symbol or intermediary.
On Love: Respect all creations and beings but never venerate (worship) them for only Singularity can be adored.
We believe:
That faith in a Supreme Being and in Existence after Death is natural to man.
That we regard the relation between God and men to be direct and immediate.
That we do not believe in the infallibility of any man or any scripture.
Whatever book contains truths calculated to ennoble the soul or elevate the character is a Brahmo's scripture, and whoever teaches such truths is his teacher and guide.
We regard the fourfold culture of man's intellect, conscience, affections, and devotion as equally important and equally necessary for his salvation.
We consider love of God and doing the will of God as equally imperative in the routine of a Brahmo's life.
We regard the culture of faith at the sacrifice of reason, or the culture of reason at the sacrifice of faith as equally defective, and as fruitful sources of evil in the religious world.
We regard the worship of one God as the highest of a Brahmo's duties and as the best of means to improve the soul and the neglect of it as a way to spiritual death.
We look upon the enjoyment of uncontrolled authority by a single individual in any religious community as a calamity, and far from looking upon freedom of thought as reprehensible, we consider it to be desirable, and regard it as a safe-guard against corruption and degeneracy.
We regard the belief in an individual being a way to salvation, or a link between God and Man, as a belief unworthy of a Theist, and those who hold such belief as unworthy of the Brahmo name.
We consider it to be blasphemy and an insult to the Majesty of Heaven to claim Divine inspiration for any act opposed to the dictates of reason, truth, and morality.
The Brahmo stands for the following (as laid down in the Trust Deed of the Brahmo Samaj):
Followers shall love Him and do His will and worship the One Absolute, the Creator, Preserver, Destroyer who is the giver of all Good in this world and the next, who is All knowing, All Pervading, Formless and Beneficent;
Followers shall not adore any created thing, thinking it to be the Supreme One;
Followers should perform good deeds - and it is through these good deeds one can serve God;
He is the One, Alone and Absolute;
The Samaj is to be a meeting ground for all sects for the worship of the One True God;
No object of worship or a set of men shall be reviled or contemptuously spoken of or alluded to in any way;
No graven image statue or sculpture carving painting picture portrait or the likeness of anything shall be admitted within;
No object animate or inanimate that has been or is or shall hereafter become or be recognised as an object of worship;
No sacrifice offering oblation of any kind or thing shall ever be permitted;
Promote, charity, morality, piety, benevolence, virtue and strengthen the bonds of union between men of all religions and creed.
In the beginning was the one God, none else, and naught but He, the Creator of all things.
He is the True, the Good, the Infinite.
He is the Eternal Lord of the universe, the All - knowing, All - pervading, All - protecting, the Almighty.
He is the Formless, Changeless, Self - contained and Perfect.
In his worship lies our good, in this world and in the next.
To love Him and do His will - this is His true worship.