Clical music... Pay Royalties?

I'm thinking about getting into the "writing scores for commercials" job, and I recently transcribed one of Bach's Chorales for a flute quartet, I obtained the original score for Soprano, Alto Tenor, and B, and, out of curiosity, if I were to record this and put it on the market for commercial use, would I need to get licenses or permission, or pay some sort of royalty?