Sermons Four and Five of the First Decade are devoted to faith.
While Bullinger provides many definitions of faith by divers authors, let me just mention (what I believe, haha) are the pertinent ones.
Bullinger explicates what he believes (and I agree) to be Paul’s words in Heb. 11:1:
St Paul saith: “Faith is the substance of things hoped for, the evidence of things not seen.” The substance, or hypostasis, is the foundation, or the unmoveable prop, which upholdeth us, and whereon we lean and lie without peril or danger. The things hoped for are things celestial, eternal, and invisible. And therefore Paul saith: Faith is an unmoveable foundation, and a most assured confidence of God’s promises, that is, of life everlasting and all his good benefits. Moreover Paul himself, making an exposition of that which he had spoken, immediately after saith: “Faith is the argument of things not seen.” An argument or proof is an evident demonstration, whereby we manifestly prove that which otherwise should be doubtful, so that in him, whom we undertook to instruct, there may remain no doubt at all.
But now touching the mysteries of God revealed in God’s word, in themselves, or in their own nature, they cannot be seen with bodily eyes; and therefore are called things not seen. But this faith, by giving light to the mind, doth in heart perceive them, even as they are set forth in the word of God. Faith, therefore, according to the definition of Paul, is in the mind a most evident seeing, and in the heart a most certain perceiving of things invisible, that is, of things eternal; of God, I say, and all those things which he in his word setteth forth unto us concerning spiritual things. – p.82
Then, after reviewing several exercitations on Paul’s definition, Bullinger arrives at his own:
Faith is a gift of God, poured into man from heaven, whereby he is taught with an undoubted persuasion wholly to lean to God and his word; in which word God doth freely promise life and all good things in Christ, and wherein all truth necessary to be believed is plainly declared. – p.84
(Notice his emphasis in both: the Word of God as the necessary & sufficient means.)
He makes the point that God uses “certain ordinary means”, that “he sendeth teachers, by the word of God to preach true faith unto them;” and, further, that it is not man, but the Holy Spirit which can “cause us with all our heart to believe that which we by his word and teaching have learned to believe.”
He correctly emphasizes the work of the Holy Spirit by quoting Augustine:
What do I now while I speak? I drive into your ears a noise of words: but unless he which is within do reveal it, what say I, or what speak I? - p.86
Again, not wanting the reader to miss the ultimate cause of faith, Bullinger admonishes:
This therefore is left unto us for a thing most certain and undoubtedly true, that true faith is the mere gift of God, which is by the Holy Ghost from heaven bestowed upon our minds, and is declared unto us in the word of truth by teachers sent of God, and is obtained by earnest prayers which cannot be tired. – p.87
Going on, Bullinger covers assent and trust before dealing with perseverance and the fact that faith does not believe all things but being “ruled and bound to the word of God,” only is a “most sure ground and settled opinion touching God and our salvation.”
He goes back over this ground, emphasizing these points and showing their precedents in scripture. The key point being that:
God’s word is the foundation of faith, faith cannot wander to and fro, and lean to every word whatsoever: for every opinion conceived without the word of God, or against God’s word, cannot be called true faith. – p.97
Ah, Sola Scriptura! Thank You, Lord!
The summary for Sermon #4 includes the two points that a) faith is a free gift of God, and b) that it believes “all that is declared in the scriptures,” and he concludes with a restatement of his (previously quoted) definition of faith.
(Sermon #5 will be covered later.)