“Perhaps you have felt already, from the tone of my letter, that I am more than ever now the bride of science. Religion to me is science, and science is religion. In that deeply-felt truth lies the secret of my intense devotion to the reading of God's natural works. It is reading Him. His will — His intelligence; and this again is learning to obey and to follow (to the best of our power) that will! For he who reads, who interprets the Divinity with a true and simple heart, then obeys and submits in acts and feelings as by an impupulse and instinct. He can't help doing so. At least, it appears so to me.”

A Week on the Concord and Merrimack Rivers http://www.gutenberg.org/dirs/etext03/7cncd10.txt (1849), Sunday

The Kitáb-I-Asmá

Soren Kierkegaard, For Self-Examination, Hong p. 26
1850s, For Self-Examination (1851), What is Required in Order to Look at Oneself with True Blessing in the Mirror of the Word?

Wer Wissenschaft und Kunst besitzt, / Hat auch Religion / Wer jene beiden nicht besitzt / Der habe Religion
As quoted in Jost Lemmerich's "Science and Conscience: The Life of James Franck" (2011), p. 261.
Variant translation: "The man who science has and art, He also has religion. But he who is devoid of both, He surely needs religion." (as quoted in "Homilies of science" by Paul Carus (1892) and The Open Court, Weekly Journal, Vol. II (1887).
Wilhelm Meister's Lehrjahre (Apprenticeship) (1786–1830)

Interview with Max Eastman in Harper's Magazine, as quoted in James Joyce (1959) by Richard Ellmann. Eastman noted "He smiled as he said that — smiled, and then repeated it."

Religion and Natural Science (1937)

Answer from Pasteur to his disciple Elie Metchnikoff when was questioned whether his approach to spontaneous generation was bound to a religious ideal. According to Patrice Debré's Luis Pasteur, 2000 https://books.google.co.uk/books?id=RzOcl-FLw30C&lpg=PP1&pg=PA176#v=onepage&q&f=false,, p. 176.
Disputed