The answer is: Thou shalt not commit adultery

Exo 20:14

The seventh commandment, "Thou shalt not commit adultery," captures the importance of fidelity within relationships, especially marriage. It points to an inherent value placed on trust and mutual commitment between partners. In the context of ancient Israel, where polygamy was common, this commandment was revolutionary. It set clear boundaries around intimacy and faithfulness, emphasizing personal loyalty over political alliances or tribal connections.

Interestingly, while the Bible lays down specific rules, it also tells stories that illustrate the complexities of human relationships. Think of David and Bathsheba; his adultery not only led to personal turmoil but had national repercussions. This highlights that the consequences of personal failings often ripple into the community.

Moreover, biblical echoes of when trust is broken stretch beyond relationships. In prophetic literature, the people of Israel are often described in metaphorical terms akin to an unfaithful spouse abandoning their connection with God. This beautifully reflects the belief that fidelity is not only a personal issue but has broader spiritual implications.

This commandment also tied closely to broader themes of justice and community well-being. The ancient Israelites functioned as a communal society, meaning that the actions of one had the potential to affect the whole group. So while "Thou shalt not commit adultery" stresses individual choices, it's also about maintaining the integrity of the community fabric. Through this lens, the ancient rule emerges with modern resonance, calling for respect across all forms of relationships today.