This is Vidas' intabulation of double choir motet "Ecce Dominus veniet" by Hieronymus Praetorius, a contemporary of Sweelinck from Hamburg.
He added multiple organistic passages, runs and florishes to make it sound like a genuine organ piece from the time of Heinrich Scheidemann (mid 17th century) North Germany.
Let us know if he succeeded.
PS Right now we're very excited to announce that our 2nd e-book is finally ready:
I Don't Have Time to Practice Organ Playing (And Other Answers from #AskVidasAndAusra Podcast). Right now it has a low introductory price of $2.99 until August 16. It's dedicated to all our students who don't have enough time in their days and still continue to practice.