What were the main disagreements between Bernard of Clairvaux and Peter Abelard?

The primary disagreements between St. Bernard of Clairvaux and Peter Abelard centered on the role of secular philosophy and logic in the study of Christian faith.1

• Use of Dialectics: Bernard, a Cistercian abbot, was deeply suspicious of the use of secular learning and philosophy in theological matters. He specifically criticized Abelard for his excessive indulgence in dialectic—the logical analysis of arguments—when addressing questions of faith.1
• Theological Methodology: Abelard pioneered a method of using logic to reconcile apparent contradictions in church teachings, most notably in his work Sic et non. Bernard and other critics viewed this approach as an erroneous and dangerous revision of traditional Christian theology.12
• Rational Analysis of Mysteries: Bernard opposed Abelard’s attempts to apply dialectical analysis to profound religious mysteries, such as the Trinity. This conflict eventually led to Abelard’s condemnation at the Council of Sens in 1140.2

While Bernard championed a doctrine of mystical love and contemplation, Abelard emphasized the power of human reason and intention, leading to a fundamental clash between monastic tradition and the emerging Scholastic approach to theology.12