As we examine the imputation of the Active Obedience of Jesus Christ, the question before us is “What does Scripture say?” Those of us who are of the Calvinistic theological tradition should be diligently seeking to sort out biblical fact from system or tradition driven conclusions. That is, if there is some belief that we hold to be biblically true and its truth is an essential part of our theological system or heritage, yet we cannot establish its validity on any text of scripture, then we must throw that belief out; perhaps even throw out our theological system; or ignore certain parts of our heritage.

Source: Examining the Imputation of the Active Obedience of Christ

See also their appendix and response to FIRE.