In this passage, Walter Scott employs an idiom and situational irony to convey Bois-Guilbert's response to Rebecca's threats to kill herself rather than submit to him. As he tries to coax her down from the tower, he makes the following vow:
The Templar hesitated, and a resolution which had never yielded to pity or distress, gave way to his admiration of her fortitude. ‘Come down,’ he said, ‘rash girl! – I swear by earth, and sea, and sky, I will offer thee no offence.’
Bois-Guilbert's use of the idiom "I swear by earth, and sea, and sky" to reassure Rebecca is a very odd one in this context. The idiom comes from the English pagan tradition, invoking the forces which make up the world to bear witness to an important promise. For a pagan, this oath might hold a great deal of importance. However, Bois-Guilbert is a Knight Templar, the most orthodox and unyielding of the Christian militias of the medieval period. In a situation as intense as this one—Rebecca is threatening to kill herself rather than let him touch her— a reader would expect him to invoke the Christian God to persuade her of his sincerity and good intentions.
However, instead of invoking the Christian Trinity (Father, Son, and Holy Spirit), Bois-Guilbert swears by the pagan triad of “earth, and sea, and sky.” Bois-Guilbert is so flustered by Rebecca’s bravery that he offers her a promise based on a belief system neither of them follow. His choice to use a non-Christian oath in such a critical moment is quite revealing. It suggests a disconnect between Bois-Guilbert's religious identity and his desires. His state of intense alarm and panic, driven by Rebecca's courage and his obsession with her, leads him to offer an oath that seems weighty, but that might not mean anything at all.
When Rebecca insists on caring for Ivanhoe after the Ashby tournament, Isaac uses an idiom to express concern for the grave situation they find themselves in due to this bold decision:
Isaac, seizing the sleeve of her mantle, again exclaimed in a hurried voice – ‘Beard of Aaron! – what if the youth perish! – if he die in our custody, shall we not be held guilty of his blood, and torn to pieces by the multitude?’
The idiom "Beard of Aaron!" draws from Jewish tradition, invoking Aaron, the brother of Moses and the first high priest in the Hebrew Bible. By using this phrase, Isaac is not just expressing his anxiety. He’s also calling upon a sacred symbol of divine grace. Aaron’s beard symbolized God’s protection; calling on Aaron suggests a plea for divine help and protection in a moment of extreme fear and uncertainty. Isaac knows that if Ivanoe were to die under Rebecca’s care they would be in great danger. He foresees the potential for blame and violent retribution from the Christians around them if Ivanhoe's death occurs while he is in their custody. Indeed, he thinks he will be “torn to pieces” if this happens. Isaac’s use of this idiom points to the deep-rooted fear of persecution that he and Rebecca face, not only as individuals but also as members of the Jewish community. Isaac's urgent plea for divine help underscores the tension and danger of their situation, which is both risky and potentially very rewarding should Rebecca succeed.
After hearing all of her reasons for wanting to nurse him herself, Isaac concedes to Rebecca's refusal to let someone else heal Ivanhoe using an idiom and allusion:
‘Thou art speaking but sooth, Rebecca,’ said Isaac, giving way to these weighty arguments – ‘it were an offending of Heaven to betray the secrets of the blessed Miriam; for the good which Heaven giveth us, is not rashly to be squandered upon others, whether it be talents of gold and shekels of silver, or whether it be the secret mysteries of a wise physician.'
The idiom "speaking but sooth" is Isaac's acknowledgment of the truthfulness of Rebecca’s reasoning for wanting to care for Ivanhoe. "Sooth" is an archaic word for "truth." Rebecca knows that Ivanhoe is a favorite of Richard I, and that saving him might redeem the family in the King’s eyes when he returns. She also doesn’t want to share the secrets of her medical preparations with anyone else. By agreeing that Rebecca is "speaking but sooth,” Isaac admits the validity of her argument. Although he is frightened, he understands why she must heal the young knight herself.
The allusion to "the secrets of the blessed Miriam" refers to the healing elixir that Rebecca has prepared for Ivanhoe. By invoking Miriam, sister of Moses in the Bible and revered in Jewish tradition for her wisdom, Isaac acknowledges the sacredness of Rebecca's knowledge and her healing abilities. This allusion suggests that her knowledge is a precious secret which links her to the historical and spiritual legacy of Miriam. Isaac's reluctance to share Rebecca's healing secrets with others is rooted in a deep respect for the sanctity and uniqueness of her skills, and an unwillingness to let her potion pass into non-Jewish hands.
As Isaac nervously speaks to Nathan Ben Samuel about visting the Preceptory of Templestowe, home of the Grand Master of the Knights Templar, Scott uses allusion and an idiom to convey the fearsome reputation Lucas de Beaumanoir commands:
‘It is well known unto me,’ answered Isaac; ‘the Gentiles deliver this Lucas Beaumanoir as a man zealous to slaying for every point of the Nazarene law; and our brethren have termed him a cruel destroyer of the Saracens, and a cruel tyrant to the Children of the Promise.’
Isaac is terrified of meeting de Beaumanoir because he has a reputation for violence and zealotry. He sees non-Christians as subhuman infidels and has killed or subjugated thousands in the Templars' name. The idiom "Children of the Promise" as Isaac uses it here is an old-fashioned term for Jews, deriving from the Biblical “promises” made to Abraham and his descendants. Although Christianity and Judaism are both Abrahamic religions, the enforcement of “Nazarene law” is a terrifying prospect for the Jewish characters in Ivanhoe.
The allusion to "Nazarene law" points to the historical animosity and persecution faced by Jews (and Muslims, whom Scott's characters call "Saracens") under Christian rule, particularly during the Crusades. "Nazarene" or Christian law refers to Nazareth, the Biblical birthplace of Jesus Christ. By characterizing Beaumanoir as someone who zealously enforces Christian laws to the detriment of Jews and Muslims, Isaac highlights the threat posed by zealots like de Beaumanoir to non-Christian communities. The reference he makes to "Nazarene law" as a justification for being a “cruel destroyer” points to the intense and wide-reaching power of the Christian church at the time. It also points to the precarious position Jewish people occupied in the Middle Ages, as a group who were often caught between conflicting powers and subjected to legal and social oppression wherever they went.
