Both pieces have BWV numbers, but they belong to a group, which also contains other composers.
These two are Bachian imho: the first with its beautiful flowing harmonies is a gem and listening to the second prelude you can imagine Bach at the organ in Arnstadt improvising his choral introduction.
00:00 Nun komm der Heiden Heiland 01:34 Herr Jesu Christ dich zu uns wend
Both on the excellent Metzler organ of Poblet Abbey; still a gem among gems....