William Chillingworth, The Religion of Protestants a Safe Way of Salvation (1637), p. 71:
16. To the third : "Whether it be not impertinent to allege the Creed as containing all fundamental points of faith, as if believing it alone we were at liberty to deny all other points of Scripture?" I answer—It was never alleged to any such purpose; but only as a sufficient, or rather more than a sufficient, summary of those points of faith, which were of necessity to be believed actually and explicitly; and that only of such which were merely and purely credenda, and not agenda.
Nathaniel Hardy, The first General Epistle of St. John the Apostle, unfolded and applied (1656-1659), p. 6:
The globe of divinity parts itself into two hemispheres, to wit, credenda et agenda, the things we are to know and believe, and the things we are to do and perform....
Richard Baxter, A Christian Directory (1673, 1846, 2000), p. 713:
6. The baptismal covenant of grace therefore is the essential part of the gospel, and of the Christian religion ; and all the rest are the integrals, and accidents or adjuncts.
7. This covenant containeth,
I. Objectively, 1. Things true as such; 2. Things good as such; 3. Things practicable or to be done, as such: the credenda, diligenda, (et eligenda,) et agenda; as the objects of man's intellect, will, and practical power.
The credenda, or things to be known and believed, are, 1. God as God, and our God and Father. 2. Christ as the Saviour, and our Saviour. 3. The Holy Ghost as such, and as the Sanctifier, and our Sanctifier (as to the offer of these relations in the covenant).
The diligenda are the same three Persons in these three relations as good in themselves and unto us, which includeth the grand benefits of reconciliation and adoption, justification, and sanctification, and salvation.
The agenda in the time of baptism that make us Christians, are, 1. The actual dedition, resignation, or dedication of ourselves, to God the Father, Son, and Holy Ghost in these relations. 2. A promise or vow to endeavour faithfully to live according to our undertaken relations (though not in perfection); that is, as creatures to their Creator, and their reconciled God and Father; as Christians to their Redeemer, their Teacher, their Ruler, and their Saviour; and as willing receivers of the sanctifying and comforting operations of the Holy Spirit.
II. The objects tell you what the acts must be on our part; 1. With the understanding, to know and believe; 2. With the will to love, choose, desire, and resolve; and, 3. Practically to deliver up ourselves for the present, and to promise for the time to come. These are the essentials of the Christian religion.
8. The creed is a larger explication of the credenda, and the Lord's prayer of the diligenda, or things to be willed, desired, and hoped for; and the decalogue of the natural part of the agenda.
John Howe, The Vanity of a Formal Profession of Religion, Considered in Eight Sermons, on Titus 1.16 (Sermon 4, 1680), in The Whole Works of the Rev. John Howe, M.A., Vol. 5, p. 479:
What a poor pretence is it when one has nothing to trust to and rely upon, as the ground of his eternal hope, but only that he is an orthodox man! An orthodox son of this or that church! So far it is well. But what does it signify to be an orthodox drunkard, an orthodox swearer, an orthodox sabbath-breaker? If such would but admit one to reason soberly with them, I would ask them, "What! do you not believe, that holiness is as essential to Christianity, as truth? Do you not think that the decalogue is of as good authority, as the articles of your creed? is there not the same authority for the agenda, as there is for the credenda of a christian? Has not any man, that owns the Christian name, as great obligations to be pious, sober, and chaste; as he has to be true, or right in his principles?" There is certainly the same authority for the one as for the other. What does a man hope he shall gain, by tearing the essential parts of the Christian religion asunder, as much as, in him lies; or by dividing Christianity from itself?
Thomas Goodwin, The Work of the Holy Ghost in Our Salvation (1681), in The Works of Thomas Goodwin, Vol. 6, p. 232:
Now as the sum of our religion is reduced by the apostle to these two, 'Faith, and a good conscience,' 1 Tim. i.19, faith, which is principium credendorum, the principle of things to be believed; and conscience, which is principium agendorum, the principle of things to be done by us; for as the object matter of all religion is reduced to credenda and agenda, so the principles within us are answerably thus generally expressed by these two, faith and conscience. Faith looks upward to the things of the gospel, and takes in all supernatural truths, with application to a man's soul. Conscience looks both inward, to our own actings within; and outward, to the law or rule which is to guide us. And it also is the spring to all the wheels, and the mover in all provocations to duties, or avocations from sins.