The Guardians of the Covenant by Tom Egeland
In the year 1013, Viking warriors raided an Egyptian tomb and unknowingly stole the greatest secret of the Old Testament.
When a quirky archaeologist finds ancient Viking parchments containing runes and riddles, his mundane life is changed for good. These codes lead him on a quest for clues in mysterious places, from Egyptian tombs to antiquarian bookshops.
Powerful forces are against him, but he manages to unveil a religious cover-up with potentially fatal consequences.