God's word teaches that the church is not called to meet and cater to the spiritual expectations of any nation, culture or competing worldview. The church is called to boldly proclaim repentance and the forgiveness of sins in Jesus Name to all nations (Luke 24:46-47). This bold and certain proclamation that Jesus is THE way, THE truth and THE life (John 14:6) flies directly in the face of the epistemological assumptions of postmodernity; particularly that objective truth is unknowable and that there is no ultimate spiritual authority.
Therefore, the church must call postmoderns just like every other lost human tribe to repentance of not only of their sins but also of their false epistemology and worldview. (2 Cor. 10:5) Biblical Christians must struggle to release postmoderns from the fog of uncertainty (Heb.11:1-2) and the mistaken belief that truth is a plurality and call them into the brilliance and glory of the singular and certain truth that Jesus Christ, the one true God (Isaiah 43:10-11) in human flesh (John 1:14) died on the cross for their sins (1 Cor. 15:3-6). He died to propitiate the wrath of God (Rom 3:23-26, Heb. 2:17) which is soon to be revealed (Rom. 2:5) and He rose again for their justification (Rom. 4:25). The proclamation of this good news, the true Biblical Gospel once and for all delivered to the saints (Jude 3), requires unwavering trust and such courage of conviction that you'd rather face Caesar's lions in the sands of coliseum than deny it (Matt. 10:33).