4 , ▁making ▁only ▁slight ▁changes ▁to ▁the ▁orch estr ation , ▁most ▁not ably ▁replacing ▁the ▁by - then ▁almost ▁ob sole te ▁vi ola ▁d ' am ore ▁with ▁m uted ▁viol ins . ▁Also , ▁Bach ' s ▁or chestra ▁for ▁this ▁piece ▁would ▁have ▁been ▁very ▁del icate ▁in ▁nature ▁because ▁he ▁called ▁for ▁many ▁g amba ▁strings . ▁ ▁In ▁the ▁summer ▁of ▁ 1 8 1 5 , ▁Bach ' s ▁Pass ions ▁began ▁to ▁be ▁studied ▁once ▁again . ▁Part s ▁of ▁the ▁St ▁John ▁Pass ion ▁were ▁being ▁re he ars ed ▁and ▁the ▁St ▁Matthew ▁Pass ion ▁was ▁soon ▁to ▁follow . ▁Fred ▁Wol le , ▁with ▁his ▁Ch oral ▁Union ▁of ▁ 1 8 8 8 ▁at ▁the ▁Mor av ian ▁town ▁of ▁Beth le hem , ▁Pennsylvania , ▁was ▁the ▁first ▁to ▁perform ▁the ▁St ▁John ▁Pass ion ▁in ▁the ▁Amer icas . ▁This ▁sp ur red ▁a ▁rev ival ▁of ▁Bach ' s ▁ch oral ▁music ▁in ▁the ▁New ▁World . ▁ ▁Cong reg ational ▁use ▁▁ ▁While ▁writing ▁the ▁St ▁John ▁Pass ion , ▁Bach ▁intended ▁to ▁retain ▁the ▁con greg ational ▁spirit ▁of ▁the ▁worship ▁service . ▁The ▁text ▁for ▁the ▁body ▁of ▁the ▁work ▁is ▁taken ▁from ▁the ▁G ospel ▁of ▁John ▁chap ters ▁ 1 8 ▁and ▁ 1 9 . ▁To ▁augment ▁these ▁chap ters , ▁which ▁he ▁summar ized ▁in ▁the ▁music , ▁Bach ▁used ▁an ▁elaborate ▁body ▁of ▁comment ary ▁consisting ▁of ▁h ym