Two letters by Albert Einstein are to be auctioned in Los Angeles on Thursday, with the Nobel Prize winning physicist musing in one about his relationship with God.

Both letters were written to his best friend Michele Besso, a Swiss/Italian engineer, and both now command a minimum bid of $60,000.

The later letter, written in 1950, sees Einstein turn to the subject of God, saying: “There is one thing that I have learned in the course of a long life: It is devilishly difficult to get closer to ‘Him’, if one does not want to remain on the surface…”

In the earlier letter, written in 1929, the Swiss-born genius skips between subjects such as cooking at home to unifying two great scientific theories on gravity and relativity.

Auction house owner Nate Sanders stated, “Much has been written about Einstein’s thoughts on religion and God. Einstein is generally credited with being an agnostic. This letter provides a unique personal glimpse into Einstein’s relationship with the divine.”