▁Sch o enberg ▁married ▁Z em lin sky ' s ▁sister , ▁Math ilde . ▁Z em lin sky ▁gave ▁Sch o enberg ▁less ons ▁in ▁counter point , ▁thus ▁becoming ▁the ▁only ▁formal ▁music ▁teacher ▁Sch o enberg ▁would ▁have . ▁ ▁In ▁ 1 8 9 7 ▁Z em lin sky ' s ▁Sym phony ▁No . ▁ 2 ▁( chron olog ically ▁the ▁third ▁he ▁had ▁written , ▁and ▁sometimes ▁number ed ▁as ▁such ) ▁was ▁a ▁success ▁when ▁premier ed ▁in ▁Vienna . ▁His ▁reputation ▁as ▁a ▁composer ▁was ▁further ▁helped ▁when ▁Gustav ▁Mah ler ▁conducted ▁the ▁premi ere ▁of ▁his ▁opera ▁Es ▁war ▁einmal ▁( Once ▁Upon ▁a ▁Time ) ▁at ▁the ▁Hof oper ▁in ▁ 1 9 0 0 . ▁In ▁ 1 8 9 9 ▁Z em lin sky ▁secured ▁the ▁post ▁of ▁Kap ell meister ▁at ▁Vienna ' s ▁Carl the ater . ▁ ▁In ▁ 1 8 9 9 , ▁Z em lin sky ▁converted ▁to ▁Protest ant ism . ▁He ▁all ud ed ▁to ▁the ▁Christian ▁cross ▁and ▁to ▁Jesus ▁in ▁the ▁text ▁of ▁Turn w äch ter lied , ▁and ▁included ▁vers es ▁from ▁Ps al ms ▁in ▁several ▁of ▁his ▁compos itions . ▁ ▁Middle ▁years ▁In ▁ 1 9 0 0 , ▁Z em lin sky ▁met ▁and ▁fell ▁in ▁love ▁with ▁Al ma ▁Sch ind ler , ▁one ▁of ▁his ▁composition ▁students . ▁She ▁reci proc ated ▁his ▁feelings ▁initially ; ▁however , ▁Al ma ▁felt ▁a ▁great ▁deal