Answer:
Religion as a generalized concept, which designate the social phenomenon and / or a world outlook of people in the relation to sacral (holy) things, can’t have any objectives.
This can be seen from the given designation of religion.
From here it becomes understandable the absurdity of definitions by Soviet power and communists of religion as “opium for people” or by V. L. Ginzburg as “obscurantism”, - in the spirit of communists.
The quite other thing is when you speak of some specific religion.
As a rule, religions have their certain purposes, which can be realized by certain people or organizations (churches).
As a rule, because for example, such thin and elusive religion as Zen-
Buddhism, doesn’t suppose formulation of some visible and rough purposes, approved on the West and strives for to some philosophic – psychological state, which is called Enlightenment (uh, satori), reached by different methods.
They can be considerations over dialogs, stripped of sense from the point of view of uninitiated (ven-do, mondo) or questions (goon-an, koan).
In the primary Buddhism, created by Siddhartha Gautama (Buddha) it was possible to designate more clear purposes, which were expressed in the especially individual efforts for the achievement of Enlightenment and, in the final result, - Nirvana – loss of sense of the individual being and absence of the desires by means of practicing meditation and thus, - liberation from sufferings.
Realization of these, seemingly such elusive purposes led to that Buddhism became a world religion, and now its followers count more than 300 million people.
But there are two purposes, which almost all religions are striving for – more wide dissemination and influence.
Almost all religions, because there is one more exclusion. It relates, in its turn, to Judaism.
Judaism from the very beginning was the religion of one people. This can be explained by that creation of this monotheistic religion, in which the main role was performed by Yahweh – the God alone, Creator and Lord of the Universe, was a revolutionary event, an extraordinary one.
Thus, at that time it was quite logically to suppose that people which “created” the God alone, has with Him, at least, confidential relations.
And from here it was not far to form idea of “Testament” – of union, covenant of the people with God, in which Jews act as carriers of the Holy Revelation.
This idea – purpose played double role in the history of Judaism: despite its revolutionary character it has strongly limited access to this religion for other people.
But namely this purpose helped Jews to remain themselves during of four thousands years.
A creation of the Bible in Judaism (Old Testament in the Western terminology)
led to that Judaism during many ages remained a great religion, which served the basis for the emergence of two world religions – Christianity and Islam and laid spiritual, moral, ethical and ideological foundations of the Western civilizations.
Having realized this limitation, Saul – Paul, creating Christian Church, pursued his main purpose – to have an instrument for dissemination of Christianity and with this purpose he introduced three new laws in relation to Judaism, canceling Jewish ones, the generalization of which was that any man and, above all, a pagan can become a Christian.
In the aftermath, the Christian sect from Jewish very quickly during 20-25 years turned into purely Christian one, and Romans ceased to see Jews in Christians and separated them into a particular religion, not connected with any nationality.
Still more after 250 years after Paul was executed, the Roman empire will be ruled by a Christian.
And then Church, being converted from victim into winner, will put a new objective before itself – actively struggle for power.
Today on Earth we can count about 2 billions of Christians, 1 billion of Muslims, 700 million of Hinduism adepts and about 14 million people, professing Judaism.