«وَيُنَافَسُ فِي الثَّمِينِ»
People compete for what is precious.
Al-thamīn means something valuable or precious. The companion begins with a general observation: we discern and protect what carries value. He applies that discernment to friendship, distinguishing a loyal companion from someone who seeks only advantage.
His point need not imply befriending only wealthy or influential people. In the argument, value points toward nonmaterial qualities such as loyalty, integrity, and genuine concern.