There are numerous indications of this interest. He is reported by multiple sources to have visited Christian Science churches and studied in the denominational reading rooms. He complimented Eddy’s writings in conversation and defended her ideas against criticism in private. He frequently visited his son and daughter-in-law who were Christian Scientists. His favorite philosophers, though conceptually distant from Eddy, nonetheless entertained certain thoughts in line with Eddy's. His recorded comments about her metaphysics, though brief and general, were invariably approving.
Does this prove that Einstein was a closet Christian Scientist? Hardly. But it is historically worthy of note that he saw something deeply intriguing in Eddy's ideas, and his interest continued over a period of many years. We can make of this what we will.
To see a scholarly paper summarizing the various clues indicative of his interest, click here. To switch back and forth between text and footnotes, click on the bracketed blue footnote numbers.