A devout Seventh-day Adventist, Blomstedt does not rehearse on Friday nights or Saturdays, the Sabbath in Seventh-day Adventism. He does, however, conduct concerts, since he considers actual performances to be an expression of his religious devotion rather than secular work.[4]
He has been Music Director or Principal Conductor of the Norrköping Symphony Orchestra (1954–1962), Oslo Philharmonic Orchestra (1962–1968), Danish Radio Symphony (1967–1977) and Swedish Radio Symphony (1977–1982). From 1975 to 1985, he served as chief conductor of the Staatskapelle Dresden, in the process making many well-regarded recordings, including works of Richard Strauss and the complete Beethoven and Schubert symphonies, and leading the orchestra on international tours.