The document discusses the concept of brotherly kindness. It defines brotherly kindness as the love of brothers from the Greek words "phileo" meaning love and "adelphos" meaning brother. It explains that the design of brotherly kindness is for others to see Christ in Christians through their love for one another. The demand of brotherly kindness is that one cannot claim to love God without also showing sincere love for other believers. Finally, the display of brotherly kindness is shown through examples from the Bible of Jonathan's deep love and commitment to David.