Filioque
In one sentence
The Western formula that the Holy Spirit proceeds from the Father and the Son, a major East-West controversy.
In simple terms
The Western formula confesses the Holy Spirit’s procession “from the Father and the Son,” while the classical Eastern formula says “from the Father.”
Biblical truth
Scripture says the Spirit proceeds from the Father, is sent by Father and Son, and is called the Spirit of the Father and of Christ; the question is how to systematize these relations.
Key Scriptures
John 14:26 · John 15:26 · John 16:7 · Rom. 8:9 · Gal. 4:6
Example
The West distinguishes eternal procession from the Spirit’s historical mission yet relates the Son to eternal procession; the East safeguards the Father as the single source of deity.
Who holds it
Western Christianity generally accepts the Filioque; Orthodox tradition traditionally rejects its insertion into the Creed and disputes its theological content.
Not to be confused with
Not to be confused with the Spirit’s eternal procession versus his temporal mission into the world.
History
The phrase was gradually added to the Western form of the Niceno-Constantinopolitan Creed and became a major East-West controversy.
Main point of debate
The dispute is both theological and ecclesial-historical: how to understand the Spirit’s relation to Father and Son, and whether the Creed could be altered unilaterally.