Francis Pieper on Intellectual Assent

 One common argument against the faith being only intellectual and assent is that it is a belief of Zane Hodges.

Basically this argument in short is that a doctrine or teaching is guilty by association. The response is that just because a person or group of people say or hold to a doctrine does not make that doctrine wrong.  Catholics teach justification and sanctification. However, Catholics don't teach it rightly. They teach that justification and sanctification are confused and that a man is saved by faith and works.

With that said the belief that Faith is intellectual and assent is Scriptural.

Lutheran theologian Francis Pieper, in his Christian Dogmatics Volume 2 Pag 430 says

"The Lutheran Confession follow the terminology of Scripture. Knowledge, according to their use, designates the entire justifying faith. The Apology thus writes: 'Faith which receives the forgiveness of sins . . . is the true knowledge of Christ' (Trigl. 133, Art. IV [II], 46). 'What is the knowledge of Christ unless we know the benefits of Christ, the promises which by the Gospel He has scattered broadcast in the world? And to know these benefits is properly and truly to believe in Christ.' (Trigl. 154, ibid., 101.) Regarding the 'assent' the Apology says: 'Faith, properly so called, is that which assents to the promise' (Trigl. 154, ibid., 113). 'That faith which justifies is . . . to assent to the promises of God' (Trigl. 134, ibid., 48). On 'confidence' the Apology says: 'To believe means to rely on the mercy of God, that He desires to be gracious for Christ's sake, without our merits' (Trigl. 207, Art III, 194). The Apology uses 'trust' and 'assent' as interchangeable terms. 'That faith which justifies is . . . to assent to the promises of God. . . . It is the certainty or the certain trust in the heart, when, with my whole heart, I regard the promises of God as certain and true.' (Trigl. 135, Art. IV [II], 48.)" - The Bold is my own for emphasis and clarity

According to Francis Pieper tohave faith is to believe and to believe is to assent, trust, rely. These things are simplistic