When “the writing is on the wall,” it usually indicates the end. For the Boston Camerata, it was just the beginning. The phrase comes from the Biblical story of Daniel, when mysterious writing appears to a corrupt leader, an omen of his demise, and has been used on countless politicians since. The ensemble performs their new interpretation of “The Play of Daniel” (c. 1200) on Jan. 19 at Grace and Holy Trinity, presented by the Friends of Chamber Music.