“Religion and science are all in pursuit of reaching the spiritual realm, thus transcending bodily things.”

These two statements are very similar, widely quoted, and seem to paraphrase some ideas in the essay "Religion and Science" (see below), but neither of the two specific quotes above been properly sourced. Notable Einstein scholars such as John Stachel and Thomas J. McFarlane (author of Buddha and Einstein: The Parallel Sayings) know of this statement but have not found any source for it. Any information on any definite original sources for these is welcome.
This quote does not actually appear in Albert Einstein: The Human Side as is sometimes claimed.
Only two sources from before 1970 can be found on Google Books. The first is The Theosophist: Volume 86 which seems to cover the years 1964 http://books.google.com/books?id=7pLjAAAAMAAJ&q=1964#search_anchor and 1965 http://books.google.com/books?id=7pLjAAAAMAAJ&q=1965#search_anchor. The quote appears attributed to Einstein on p. 255 http://books.google.com/books?id=7pLjAAAAMAAJ&q=%22natural+and+spiritual%22#search_anchor, with the wording given as "The religion of the future will be a cosmic religion. It should transcend a personal God and avoid dogmas and theology. Covering both the natural and the spiritual, it should be based on a religious sense arising from the experience of all things, natural and spiritual, as a meaningful unity. Buddhism answers this description." An identical quote appears on p. 284 http://books.google.com/books?id=YpsfAQAAIAAJ&q=%22dogmas+and+theology%22#search_anchor of The Maha Bodhi: Volume 72 published by the Maha Bodhi Society of India, which seems to contain issues from throughout 1964 http://books.google.com/books?id=YpsfAQAAIAAJ&q=%22volume+72%22#search_anchor.
A number of phrases in the quote are similar to phrases in Einstein's "Religion and Science". Comparing the version of the quote in The Theosophist to the version of "Religion and Science" published in 1930, "a cosmic religion" in the first resembles "the cosmic religious sense" in the second; "transcend a personal God" resembles "does not involve an anthropomorphic idea of God"; "covering both the natural and the spiritual" resembles "revealed in nature and in the world of thought"; "the experience of all things, natural and spiritual, as a meaningful unity" resembles "experience the totality of existence as a unity full of significance"; and "Buddhism answers this description" resembles "The cosmic element is much stronger in Buddhism". These phrases appear in the same order in both cases, and the ones from "Religion and Science" are all from a single paragraph of the essay.
Misattributed
Variant: The religion of the future will be a cosmic religion. It should transcend a personal God and avoid dogmas and theology. Covering both the natural and the spiritual, it should be based on a religious sense arising from the experience of all things, natural and spiritual as a meaningful unity. If there is any religion that would cope with modern scientific needs, it would be Buddhism.

What We Have To Lose http://www.city-journal.org/html/11_4_what_we_have.html (Autumn 2001).
City Journal (1998 - 2008)

An Old Chaos: Humanism and Flying Saucers (p. 77)
The Silence of Animals: On Progress and Other Modern Myths (2013)

The New Divinity (1964)
Context: The entire cosmos is made out of one and the same world-stuff, operated by the same energy as we ourselves. "Mind" and "matter" appears as two aspects of our unitary mind-bodies. There is no separate supernatural realm: all phenomena are part of one natural process of evolution. There is no basic cleavage between science and religion; they are both organs of evolving humanity.

Source: The Self-Overcoming of Nihilism (1990), p. 163

Source: The Gospel of Sri Ramakrishna (1942), p. 111
Context: God can be realized through all paths. All religions are true. The important thing is to reach the roof. You can reach it by stone stairs or by wooden stairs or by bamboo steps or by a rope. You can also climb up by a bamboo pole.

Life-Study of Luke, Chapter 29, Section 2, of Witness Lee - By Living Stream Ministry, ISBN 0-7363-1202-1

Seien Sie außer Sorge, nach Kanossa gehen wir nicht, weder körperlich noch geistig.
Speech to the Reichstag (14 May 1872), Ausgewählte Reden des Fürsten von Bismarck: p. 176 https://books.google.com/books?id=nsjCDgAAQBAJ&pg=PA176&lpg=PA176&dq=Kanossa-rede&source=bl&ots=f3X5xq7raK&sig=Y86H5ZlgredQfpC3Wa_AB2Z-fOM&hl=en&sa=X&ved=0ahUKEwiIhrCn56zaAhVs3IMKHdBnAWwQ6AEIQTAC#v=onepage&q=Kanossa-rede&f=false, referring to the controversy over the Imperial envoy to the Holy See, Prince Hohenlohe, who had been rejected by Pope Pius IX, which marked the beginning of the Prussian Kulturkampf. The expression highlighted an era of political struggle between the Catholic Church and various secular governments, especially severe throughout the 1870s.
1870s

Aham Da Asmi