This is he of whom it is written, Look! I send my messenger before your face, who will prepare the road before you.a Bible see other translations
From Mal. 3:1

“Look!” The Greek word is idou (#2400 ἰδού), and it is used to get our attention. See commentary on Matthew 1:20.

“I send my messenger.” This is quoted from Malachi 3:1.

“who will prepare the road.” See commentary on Mark 1:3.

Commentary for: Matthew 11:10