Plain definitions for terms used in the articles, plus a few topics worth understanding on their own.
Words that show up repeatedly across the site without always being explained where they appear.
The single shared essence or being of God. What is common to the Father, the Son, and the Holy Spirit.
A distinct person within the Trinity. Father, Son, and Spirit are three hypostases sharing one ousia.
"“Of one essence.” The term used by the Council of Nicaea to affirm that the Son shares the same divine essence as the Father.
Participation in divine life through grace. Orthodox theology describes theosis as becoming like God without becoming God in essence.
God's essence, forever unknowable in itself, and his energies, his uncreated activity through which he is genuinely known and experienced.
The honour given to icons and saints. In Orthodox theology, this honour is directed toward the person represented and is distinguished from worship, which belongs to God alone.
Worship in the full sense. Reserved for God alone, never given to icons, saints, or anything created.
Describing God by saying what he is not, since positive language always falls short of what he actually is.
Describing God through positive statements. God is good, God is love, God is simply.
A council recognized as representing the whole Church, not one region, with authority to settle major doctrinal disputes.
Relating to the Church Fathers and their writings. The Church Fathers Library on this site covers several of them directly.
A thing that exists but does not exist necessarily. A contingent thing could have failed to exist and depends upon an explanation outside itself.
Something that exists necessarily rather than depending upon another cause or condition for its existence. Classical theism identifies the necessary foundation of reality with God.
Latin for "and the Son." The disputed phrase added to the Nicene Creed in the West, describing the Spirit as proceeding from the Father and the Son.
The word gets used loosely online. Here's the actual distinction this site works from.
Two claims that cannot both be true, at the same time, in the same sense. If Scripture said Judas both did and did not hang himself, in the exact same sense, that would be a real contradiction with no way around it.
Two claims that look incompatible on the surface but rest on different genres, different time frames, different senses of a word, or details each source simply left out. Once that context is supplied, the tension resolves without forcing either text to say something it does not.
Most items on popular "Bible contradiction" lists turn out to be apparent, not real, once genre and context are accounted for. That's the actual work most of the essays on this site are doing, not explaining away real problems, but showing that the supposed contradiction was never as tight as the list made it look.
The essays on this site mostly live in two of these. Here's the full map.
What exists, and what it means to exist at all. Questions about being, causation, time, and God fall here. Most of this site's metaphysics essays sit in this branch.
How we know what we know, and what actually counts as a simplyified belief rather than a lucky guess.
What makes an action right or wrong, and what a genuinely good life looks like. The moral argument essay on this site draws directly from this branch.
The structure of valid reasoning itself, independent of whatever subject the reasoning happens to be about.
Whether God exists, and how religious claims can be evaluated using the same philosophical tools used everywhere else. Most of this site's metaphysics essays technically sit here too.
The nature of beauty, art, and taste, and whether judgments about them can be objectively right or wrong.
The study of how authority, justice, and the state should be organized, including the obligations of government toward the people it governs.
Frequently misunderstood, on both sides of the God debate.
The Big Bang model holds that the universe began expanding from an extremely hot, extremely dense initial state, roughly 13.8 billion years ago, and has been expanding and cooling ever since. It's not an explosion happening inside empty space. It's space itself expanding, carrying galaxies apart as it does.
Three main pieces of evidence anchor the model. The cosmic microwave background, a faint radiation glow left over from the early universe, detected in every direction we look. The redshift of distant galaxies, showing the universe is expanding, discovered by Edwin Hubble. And the observed abundance of light elements like hydrogen and helium, which matches what the model predicts should have formed in the universe's first few minutes.
The Big Bang model was first proposed by Georges Lemaître, a Catholic priest and physicist, in 1927. Some scientists at the time, including Einstein initially, resisted the idea partly because it sounded uncomfortably close to a universe having a beginning, a starting point science had not needed to account for before.
The model describes what happened after the initial state. It does not, by itself, explain why there was an initial state at all, or why the laws of physics that governed the expansion exist in the first place. That's the specific gap the contingency argument and the argument from efficient cause, both covered in the Articles section, are aimed at.
The major branches, and what sits underneath each one.
The largest single Christian body, under the Pope in Rome. The Catholic Church is in communion with the Pope in Rome and includes several liturgical traditions, including the Roman and Eastern Catholic rites.
The Orthodox Church is a communion of self-governing churches that share the same faith, worship, and Ecumenical Councils. Greek, Russian, Serbian, Romanian, and Antiochian churches are among its largest jurisdictions. Russian, Greek, Serbian, Romanian, and Antiochian Orthodox are among the largest. The Oriental Orthodox churches, including Coptic and Armenian, sit in a related but doctrinally distinct family, separated after the Council of Chalcedon in 451.
The most fragmented branch, since it began as a series of separate breaks from Rome in the 1500s. Major families include Lutheran, Reformed or Calvinist, Anglican, Baptist, Methodist, Pentecostal, and the broad, deliberately unaffiliated category of Non-denominational churches.
Bodies like Latter-day Saints and Jehovah's Witnesses are sometimes classed separately, since mainstream Christian bodies dispute whether they are Trinitarian Christian in the historic sense at all.
If something on this site used a word you had to look up elsewhere, tell me and it goes here.
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