my opinion

Freemasonry and Religion
If you consider that Freemasonry - as we know it today - is a product of the 17th century and we realise that enverything then had religious overtones, it is natural that a 21st century mind perceives that Freemasonry is religious. Also please understand that Freemasonry is not dogmatic; each Freemason is free to maintain his own interpretation and perception of the Supreme Being.

Freemasonry is Not Religious
I put forth that it is an error of Modern thought that leads people to see Freemasonry as a religion or religious. Freemasons do engage in prayer, but it is not pray for Salvation. Rather, the prayer Freemasons engage in is for God's support in their pursuit of Freemasonry. Recalling that Freemason's ritual is a product of 17th century sensibilities, it is natural that God's blessing be sought prior to any endeavour.

Some Links
If you look at the following links, you will see that many Freemasons themselves are blind to the contextual issues that lead people to perceive Freemasonry to be a religion:

Grand Lodge of Victoria's Statement

The Masonic Information Centre's Statement

Freemasonry is Concerned with Mortal Issues Only
The lessons taught by Freemasonry have to do with living a good life and building friendly relations with all other people.

Freemasons believe in God
Some refer to the Supreme Being as God and others have been raised in traditions that follow a different lexicon and faith. Freemasonry recognises that these mortal attempts to know the Supreme Being are imperfect and influenced by the dominant discourse in different societies. Acknowledging the rights of individuals, Lodges ensure that the sacred books of their members are present as appropriate during Masonic Ceremonies. As an example of this practice, a scroll in the anteroom of Lodge Singapore No. 7178 E.C. describes the Volumes of the Sacred Law reposing in the Lodge Room and is accompanied by an explanation:-

The Sacred Volumes reposing in this Lodge are at this present time (1968) six in number and are as follows:

(1) The Holy Book of the Sikhs, being the Sri Guru Sahib. There have been relatively few Exaltations of Sikhs in this Lodge and until this volume was presented to the Lodge the Holy Bhagvada Gita had been used.

(2) The Holy Bhagvada Gita is the Holy Book of the Hindus and this Volume may be opened and touched by hand but not by the lips.

(3) The Khordeh Avesta of the Zoroastrian Faith being the Holy Book of the Parsees, may be treated in the same way as the Holy Bible of the Christian Faith.

(4) The Holy Koran of the Muslims. With regard to touching and sealing the Holy Koran, an overall picture is somewhat difficult to convey as the customs vary in different countries. The Imam of Kedah has, however, stated that the Holy Koran should be held above the head of the person taking an oath that such a person may neither touch nor seal it. Another accepted method of dealing with this problem is the the V.S.L. to be treated in exactly the same manner as with the Holy Bible, but with the difference that the Holy Koran should be covered. Obviously, it is the duty of the Sponsors to ascertain the method appropriate for our particular purpose.

(5) The Holy Bible of the Christians which comprises two parts, i.e. the Old Testament and the New Testament. As regards the Craft, it is the Old Testament which is acted upon. The Books of the Old Testament, which are contained in the Holy Bible are treated by those of the Jewish Faith in the same manner as by the Christians.

(6) There are two main sects of Buddhists, i.e. the Hinayana and the Mahayana. The former are from Indian, Ceylon, Burma, Cambodia and Thailand, and the Mahayana (Northern) generally hail form China, Korea and Japan. The Hinayana do not recognize a Supreme Being, but there may of course be exceptional cases. The Mayana sect acknowledges a Supreme Being and their Holy Book is the Dhammapada; being the 1st Book of the original twelve containing 423 Dhamma Stanzas. On good authority, it is understood there would be no objection to using the Holy Bible for the purpose of taking oaths, should the Dhammapada not be available.

Author Unknown. From collection and submitted by D. Roy Murray King Solomon Lodge, No. 58, GRS Victoria Lodge, No. 13, GRA

The way to Salvation is Through Religion not Freemasonry
Freemasonry is not concerned with Salvation