Dimmed Light; Dark Darkness

PM sermons are preceded by a Confessional, Catechism, or Historic Creed lesson. Usually 5 minutes or so. WCF:
5:7 As the providence of God doth, in general, reach to all creatures, so, after a most special manner, it taketh care of his Church, and disposeth all things to the good thereof.
25:4-5 This catholic Church hath been sometimes more, sometimes less visible.a 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.
5. The purest churches under heaven are subject both to mixture and error; and some have so degenerated as to become no churches of Christ, but synagogues of Satan. Nevertheless, there shall be always a Church on earth to worship God according to his will.