According to tradition, Lambert became a martyr to his defence of marital fidelity. The Bollandists, Mabillon, Valois, Lecointe, Pagi and others held, however, that the saint was killed by Frankish nobles in revenge for the failure of a plundering expedition. Kurth in 1876 critically examined the centuries-old tradition and, documents in hand, proved beyond further doubt that Lambert was martyred because of his defence of the marriage tie. READ MORE.