Scots Confession 18.7-9
The notes of the true Kirk, therefore, we believe, confess, and avow to be: first, the true preaching of the Word of God, in which God has revealed himself to us, as the writings of the prophets and apostles declare; secondly, the right administration of the sacraments of Christ Jesus, with which must be associated the Word and promise of God to seal and confirm them in our hearts; and lastly, ecclesiastical discipline uprightly ministered, as God's Word prescribes, whereby vice is repressed and virtue nourished.
Westminster Confession of Faith Ch. 25
Of the Church.
I. The catholic or universal Church, which is invisible, consists of the whole number of the elect, that have been, are, or shall be gathered into one, under Christ the head thereof; and is the spouse, the body, the fullness of Him that filleth all in all.
II. The visible Church, which is also catholic or universal under the Gospel (not confined to one nation, as before under the law), consists of all those throughout the world that profess the true religion; and of their children: and is the kingdom of the Lord Jesus Christ, the house and family of God, out of which there is no ordinary possibility of salvation.
III. Unto this catholic and visible Church, Christ hath given the ministry, oracles, and ordinances of God, for the gathering and perfecting of the saints, in this life, to the end of the world; and doth by his own presence and Spirit, according to his promise, make them effectual thereunto.
IV. This catholic Church hath been sometimes more, sometimes less, visible. And particular Churches, which are members thereof, are more or less pure, according as the doctrine of the gospel is taught and embraced, ordinances administered, and public worship performed more or less purely in them.
V. The purest Churches under heaven are subject both to mixture and error: and some have so degenerated as to become apparently no Churches of Christ. Nevertheless, there shall be always a Church on earth, to worship God according to his will.VI. There is no other head of the Church but the Lord Jesus Christ: nor can the Pope of Rome in any sense be head thereof; but is that Antichrist, that man of sin and son of perdition, that exalteth himself in the Church against Christ, and all that is called God.