How do we know that God’s Church will not be defeated?

The assurance of the Church's safety and ultimate triumph lies fundamentally in the completed work of Christ. As stated in Revelation and other scriptures, Christ declared, 'It is finished,' affirming that He fulfilled the redemptive plan set forth by God. Consequently, He has been given all authority, signifying that everything occurs under His sovereign rule and control. This divine authority means that no matter the attacks or tribulations faced by the Church, it remains secure in His victory.
Moreover, Romans 8 assures believers that they are more than conquerors through Christ who loves them. Even though the Church may encounter significant persecution, it cannot be ultimately defeated. The lack of visible success does not equate to failure; rather, it is a call to remain steadfast in faith, trusting in God’s promise that His kingdom will ultimately prevail.