In this saying, Jesus emphasizes God’s boundless knowledge and care toward every detail of our life. It also shows that God knows about us with such depth that even we ourselves cannot know. This is an exhortation for us to trust God fully, knowing that He is concerned even with the smallest details of our life. If God takes care even of the hairs of our head, we can be sure that He will also take care of all our needs and difficulties, which encourages us to live without fear and anxiety.