3 8 , ▁Sp ils bury ▁founded ▁the ▁first ▁particular ▁Bapt ist ▁church ▁in ▁London . ▁ ▁Sch olar ly ▁work ▁From ▁Sp ils bury ' s ▁past oral ▁doctrine , ▁two ▁issues , ▁exp ans ively ▁developed , ▁received ▁force ful ▁treatment : ▁the ▁constitution ▁of ▁a ▁Christian ▁con greg ation ▁and ▁the ▁" inv inci ble ▁effic acy " ▁of ▁Christ ' s ▁work ▁for ▁His ▁people . ▁ ▁In ▁ 1 6 4 3 , ▁Sp ils bury ▁published ▁A ▁Tre at ise ▁Conc ern ing ▁the ▁Law full ▁Sub ject ▁of ▁Bapt isme , ▁which ▁he ▁re iss ued ▁in ▁a ▁second ▁edition ▁in ▁ 1 6 5 2 , ▁" Cor rect ed ▁and ▁en larg ed ▁by ▁the ▁Author ." ▁ ▁In ▁ 1 6 4 6 ▁he ▁issued ▁God ' s ▁Ord in ance , ▁The ▁Sain ts ▁Priv ile ge , ▁with ▁a ▁discussion ▁of ▁what ▁he ▁perce ived ▁as ▁the ▁two ▁Script ur ally - based ▁sacr aments ▁of ▁the ▁Christian ▁church . ▁Benjamin ▁C ox e ▁trans cribed ▁and ▁en larg ed ▁the ▁second ▁part ▁of ▁this ▁work . ▁ ▁Bel ie ver ' s ▁bapt ism ▁Sp ils bury ' s ▁presentation ▁of ▁bel ie ver ' s ▁bapt ism ▁by ▁imm ersion ▁of ▁necessity ▁engaged ▁c oven antal ▁the ology . ▁ ▁He ▁approved ▁c oven ant ▁the ology ▁and ▁built ▁his ▁doctrine ▁of ▁the ▁church ▁on ▁the ▁" inf al li ble ▁certain ty " ▁of ▁the ▁et ernal ▁c