In his Systematic Theology, Wayne Grudem writes:
“The sufficiency of Scripture reminds us that nothing is sin that is not forbidden by Scripture either explicitly or by implication.
Whenever we add to the list of sins that are prohibited by Scripture itself, there will be harm to the church and to the lives of individual believers. The Holy Spirit will not empower obedience to rules that do not have God’s approval from Scripture, nor will believers generally find delight in obedience to commands that do not accord with the laws of God written on their hearts. In some cases, Christians may repeatedly and earnestly plead with God for “victory” over supposed sins that are in fact no sins at all, yet no “victory” will be given, for the attitude or action in question is in fact not a sin and is not displeasing to God. Great discouragement in prayer and frustration in the Christian life generally may be the outcome.
In other cases, continued or even increasing disobedience to these new “sins” will result, together with a false sense of guilt and a resulting alienation from God. Often there arises an increasingly uncompromising and legalistic insistence on these new rules on the part of those who do follow them, and genuine fellowship among believers in the church will fade away. Evangelism will often be stifled, for the silent proclamation of the gospel that comes from the lives of believers will at least seem (to outsiders) to include the additional requirements that one must fit this uniform pattern of life in order to become a member of the body of Christ.”