What has the church believed?

Is the bishop of Rome merely first in honor — or does he hold universal jurisdiction over the whole church?

Who is Mary — and what may the church say, and pray, about her?

What does the church owe Caesar — and what may Caesar demand of the church?

Who may minister in Christ's name — and what does ordination make of them?

'You are Peter, and on this rock I will build my church' — is the rock Peter himself, his confession of faith, or Christ?

What is the church — the institution, the elect, the gathered believers? And is there salvation outside it?

How are Israel, the covenants, Christ, and the church related within one history of salvation?

Does communion with the saints include remembrance, relics, invocation, and heavenly intercession—or only imitation of their faith?

Who may decide for the church, how does a council become authoritative, and how should error and misconduct be disciplined?

What is the difference between evangelism and missions—and why do Christian traditions disagree about proclamation, conversion, church planting, sacraments, service, justice, and dialogue?

What does baptism do, and who should receive it — infants of believing households, or believers alone?

When the church takes bread and cup and says 'This is my body' — what happens?

May God and the saints be depicted — and may the depictions be venerated?

What is a sacrament — and are there two, seven, or something else entirely?

How did repentance become public discipline, private confession, sacramental penance, evangelical conversion, and spoken absolution?

How did Christian worship develop from first-day gatherings into liturgical families, Reformation services, and modern worship movements?

Should Christians expect healing through anointing, sacrament, medicine, relic, providence, or charismatic gift?

How did Christian prayer become liturgical hours, contemplative traditions, Reformation devotion, revival prayer, and modern charismatic practice?

Is final judgment eternal conscious punishment — or could it be destruction, or even, in the end, restoration?

Is the Christian hope an immaterial paradise for souls — or a resurrected life in a renewed creation? And what does it mean to 'see God'?

What happens between death and resurrection — and can the living help the dead?

Will Christ reign on earth for a thousand years — and how should the church wait for him?

Who is Jesus Christ — and how is the one God also three?

Does the Holy Spirit proceed from the Father alone — or from the Father and the Son?

Is God impassible, immutable, and timeless — and what do we do with a Bible in which God grieves, repents, and waits?

Does God govern everything that happens — including evil — and how is he not its author?

Where does final authority lie — in Scripture alone, or in Scripture carried within the church's living tradition?

How is a sinner set right with God — by faith alone, or by faith working through love?

Does God choose who will be saved — and if so, what is left of human freedom?

How does the death of Christ save — a ransom, a satisfaction, a punishment borne, a victory won, an example given?

How holy can a Christian actually become — and can a true believer finally be lost?

What did the church mean when it confessed that Christ descended to the dead, rose bodily, ascended, and reigns?

How does salvation take hold of a person—and how may anyone know that it has?

What place does God's law have after Christ—and how are command, grace, conscience, and freedom related?

Who can be saved beyond the church's visible boundaries—and what does 'outside the Church no salvation' mean?

What do the six days mean — and did God create from nothing?

What is the image of God in us — reason, rule, relationship? And are we souls in bodies, or embodied wholes?

What did Adam's sin do to the rest of us — corrupt us, condemn us, or merely example us?

How did Christians understand marriage, consecrated celibacy, divorce, and remarriage—and why did their disciplines diverge?

How did biblical messengers and powers become Christian doctrines of angels, demons, hierarchies, exorcism, and spiritual warfare?

Who is the Holy Spirit — and did prophecy, tongues, and healing cease with the apostles?

How did baptism, laying on of hands, anointing, confirmation, and baptism in the Spirit become related—and separated?