The answer is: Oaths

Matt 5:36

In Matthew 5:36, when Jesus mentions that we cannot change the color of even one hair on our heads, he's emphasizing the limits of human control over life. This fits into a broader theme of humility and acknowledgment of our true power—or lack thereof—in the grand scheme of things. It’s not merely a whimsical reflection on hairstyles! Jesus is guiding his followers to understand that asserting control through oaths and promises can often lead us away from authenticity and simplicity.

Imagine in that time, oaths were a significant part of Jewish law and culture. Jesus encourages his audience instead to let their “yes” be yes and their “no” be no, which signifies that our word and integrity matter more than complicated proclamations. He points out that one’s sincerity shouldn’t depend on the gravity of oaths; honesty should be baked right into every interaction.

An interesting side note connects this teaching with the Jewish practice of making vows, as found in Ecclesiastes 5:5, highlighting a common slog for individuals to uphold their vows due to the social and spiritual pressure surrounding them. So, Jesus provocatively flips this tradition—suggesting that honesty and simplicity should really be our guiding principles, contrasting the showiness that negotiations often ensue. Ultimately, it's worthwhile to remember the importance of personal integrity over human capacities—or limitations, for that matter!