Romans 10:2
A few good links I've discovered on 'zeal according to knowledge':
"Zeal According to Knowledge," Shane Rosenthal (Modern Reformation 1991)
"Christian Zeal," J. C. Ryle (Tony Cappocia 2001)
"Zeal an Essential Virtue of a Christian," Jonathan Edwards (Works, Vol. 22, 1740)
"How to Submit to the Righteousness of God," John Piper (Desiring God 2003)
"Zeal According to Knowledge," Shane Rosenthal (Modern Reformation 1991)
"Christian Zeal," J. C. Ryle (Tony Cappocia 2001)
"Zeal an Essential Virtue of a Christian," Jonathan Edwards (Works, Vol. 22, 1740)
"How to Submit to the Righteousness of God," John Piper (Desiring God 2003)