According to evangelical Christian belief, the most-likely author of Isaiah 1:16-17 is the prophet Isaiah himself. The book of Isaiah is traditionally attributed to him, and evangelical Christians ascribe its authorship to the prophet who lived during the 8th century BC. Evangelicals believe that Isaiah was called by God to prophesy to the nation of Judah, warning them of God’s judgment for their sins and calling them to repentance.

In Isaiah 1:16-17, the prophet urges the people to wash themselves and make themselves clean, to remove the evil of their deeds from before God’s eyes, and to cease doing evil and learn to do good. This passage reflects the prophetic message of Isaiah, calling the people to turn away from their sinful ways and return to God.

Evangelical Christians view the book of Isaiah as a crucial part of the Old Testament, containing prophecies about the coming Messiah and the ultimate redemption through Jesus Christ. They believe that Isaiah’s message of repentance and redemption is relevant for people today, and they seek to apply its teachings to their own lives.