John Mark
Mark 1:2ESV·traditional attribution

As it is written in Isaiah the prophet, “Behold, I send my messenger before your face, who will prepare your way,

Matthew Henry Presbyterian @wholebiblehenry

We may observe here, I. What the New Testament is - the divine testament, to which we adhere above all that is human; the new testament, which we advance above that which was old. It is the gospel of Jesus Christ the Son of God, Mar 1:1. 1. It is gospel; it is God's word, and is faithful and true; see Rev 19:9; Rev 21:5; Rev 22:6.

Commenting on Mark 1:1-8

John Gill Reformed Baptist @doctorgill

As it is written in the prophets,.... Malachi and Isaiah; for passages out of both follow; though the Vulgate Latin, Syriac, and Persic versions read, "as it is written in the prophet Isaias"; and so it is in some Greek copies: but the former seems to be the better reading, since two prophets are cited, and Isaiah is the last; to which agree the Arabic...

Albert Barnes Presbyterian @notesbybarnes

Verses 2,3 As it is written in the prophets. He mentions prophets, here, without specifying which. The places are found in ; and in . . (b) "in the prophets"