What Old Testament prophet did not sin?

Answer 1

There has Never been a person, other than Jesus Christ who has walked this Earth and has not sinned.

Romans 3:23 For all have sinned, and come short of the glory of God;

Psalms 14

2The LORD looked down from heaven upon the children of men, to see if there were any that did understand, and seek God.

3They are all gone aside, they are all together become filthy: there is none that doeth good, no, not one.

There have been, however a few men who walked very close to God and dis their best to keep all of His laws and commandments. And there are even a few whom God has referred to as being perfect, but we must understand that these people were still sinners.

Genesis 17:1 And when Abram was ninety years old and nine, the LORD appeared to Abram, and said unto him, I am the Almighty God; walk before me, and be thou perfect.

1 kings 15:14 But the high places were not removed: nevertheless Asa's heart was perfect with the LORD all his days

Job1:1 There was a man in the land of Uz, whose name was Job; and that man was perfect and upright, and one that feared God, and eschewed evil.

Matthew 5:48 Be ye therefore perfect, even as your Father which is in heaven is perfect.

Luke 1

5THERE was in the days of Herod, the king of Judaea, a certain priest named Zacharias, of the course of Abia: and his wife was of the daughters of Aaron, and her name was Elisabeth.

6And they were both righteous before God, walking in all the commandments and ordinances of the Lord blameless.