The answer is: Oaths

Matt 5:36

When Jesus mentions not being able to make a single hair on your head black or white in Matthew 5:36, he’s highlighting the futility of swearing oaths and trying to control aspects of our lives that are ultimately beyond our control. It’s a clever way to teach us about humility and the importance of sincerity in speech—in other words, let your ‘yes be yes, and your no be no' (Matt 5:37).

Think about it: how often do we rely on oaths or grand statements to convince others of our integrity? Jesus is pushing back against that impulse. After all, what's the point of swearing an oath if we can't even manage the simplest aspects of reality—like our own hair color? In the larger context of the Sermon on the Mount, Jesus consistently asks us to delve deeper than mere human practices; he invites us into a form of authenticity that requires deep, genuine conviction.

Fun fact: Jesus’ teachings, particularly from this sermon, still resonate widely. For instance, the expression “the power of a pinky swear” also reflects this notion of trustworthiness! Additionally, the metaphor of hair connects us to passages across scripture, where hair symbolizes youth, vitality, and sometimes, the visibles signs of covenant—think of Samson, who lost his strength with his hair cut.

In the end, it's all about honesty and character—two qualities Jesus deems invaluable to live a life in truth.