“Look!” The Greek word is idou (#2400 ἰδού), and it is used to get our attention. See commentary on Matthew 1:20 (“Look!).
“a ruler came and bowed down before him.” Jairus had a great need, and showed respect to Jesus in asking for his help. For more on this event occurring in Capernaum, see commentary on Luke 8:40.
“bowed down before.” The synagogue leader did not think Jesus was God and likely did not even believe he was the Messiah, but rather was paying him homage, as he would to a superior, or to a prophet of God. See commentary on Matthew 2:2.