¥Malachi speaks of 'my messenger' who will prepare the way 'before me.'
–It is the LORD who is here speaking.
¥Mark applies this to Jesus, see verses 7-8:
–7 (NIV) And this was his [John's] message: "After me will come one more powerful than I, the thongs of whose sandals I am not worthy to stoop down and untie. 8 I baptize you with water, but he will baptize you with the Holy Spirit."