What are the marks of a true church according to the Bible?

According to the Bible, a true church is characterized by its commitment to sound doctrine, including the faithful preaching of the gospel and Scriptures. This means the church must teach the truth of Christ's person and work, confirming the importance of His righteousness as the foundation of salvation. Additionally, a true church regularly practices the ordinances of baptism and the Lord's Supper, ensuring that these acts reflect the believer's faith in Christ. Discipline is also a vital aspect, exercised in love, which helps to maintain the purity and integrity of the church, providing a means of accountability among its members.