Of Prayer, by John Calvin, tr. Henry Beveridge , at sacred-texts.com
Moreover since he himself is the only way and the only access by which we can draw near to God, those who deviate from this way, and decline this access, have no other remaining; his throne presents nothing but wrath, judgment, and terror. In short, as the Father has consecrated him our guide and head, those who abandon or turn aside from him in any way endeavour, as much as in them lies, to sully and efface the stamp which God has impressed. Christ, therefore, is the only Mediator by whose intercession the Father is rendered propitious and exorable (1 Timothy 2:5). For though the saints are still permitted to use intercessions, by which they mutually beseech God in behalf of each other's salvation, and of which the Apostle makes mention (Eph. 6:18, 19; 1 Timothy 2:1); yet these depend on that one intercession, so far are they from derogating from it. For as the intercessions which, as members of one body we offer up for each other, spring from the feeling of love, so they have reference to this one head. Being thus also made in the name of Christ, what more do they than declare that no man can derive the least benefit from any prayers without the intercession of Christ? As there is nothing in the intercession of Christ to prevent the different members of the Church from offering up prayers for each other, so let it be held as a fixed principle, that all the intercessions thus used in the Church must have reference to that one intercession. Nay, we must be specially careful to show our gratitude on this very account, that God pardoning our unworthiness, not only allows each individual to pray for himself, but allows all to intercede mutually for each other. God having given a place in his Church to intercessors who would deserve to be rejected when praying privately on their own account, how presumptuous were it to abuse this kindness by employing it to obscure the honour of Christ?