marsalis: marcus told me that you were never about self-pity or feeling bad about yourself. >> coretta robertsi mean, she could do a lot of stuff that to this day i can't really do. like, she can iron clothes, she can cook, she knows how to, like, run a household. >> marsalis: he taught himself enough to get his first gig at the silas missionary baptist church, on this very piano. it's out of tune but still quite soulful. ♪ ♪ >> sister murray: i remember him. >> marsalis: sister murray used to lift marcus up on the piano bench. his mama said, when he first started playing, he didn't sound good. >> murray: ooh. he got better. he could really play and he could sing. >> marsalis: oh, he could sing at the same time? >> murray: oh, yeah. >> marsalis: and then, where you hold chords out is real important in gospel music. so they'll be playing... ♪ ♪ he learned the gospel style-- music for praise, for consolation, and for teasing a few more coins into the collection plate. when you really wanted the church to get more intensity, give me an example of something you would do to have some intensity to i