Matthew 9:10-13, "And it came to pass, as Jesus sat at meat in the house, behold, many publicans and sinners came and sat down with him and his disciples. And when the Pharisees saw it, they said unto his disciples, Why eateth your Master with publicans and sinners? But when Jesus heard that, he said unto them, They that be whole need not a physician, but they that are sick. But go ye and learn what that meaneth, I will have mercy, and not sacrifice: for I am not come to call the righteous, but sinners to repentance."
Does Matthew 9:13 teach repentance from sin? Someone asked me this question recently. The answer is, No absolutely not. We must also include verses 10-12 with verse 13. As a habit when studying the Bible, NEVER lift a text out of context lest you create a new context. The way to avoid this error is to simply read the entire passage. Many heresies could be avoided if Bible students would simply get into the habit of ALWAYS reading an entire passage before concluding what a particular Bible verse means. I see false teachers do this all the time, lifting a single Bible verse out of context to support a particular heresy, while totally ignoring the rest of the related passage.
In Matthew 9:13 Jesus simply meant that He didn't come to save self-righteous people who don't see themselves as guilty sinners. Jesus came to save sinners (Luke 19:10). Jesus came to die for ungodly sinners (Romans 5:6-9). The word “repentance” here is the Greek noun metanoia, which means "a change of mind." The word never means “to turn away from sin” concerning salvation in the Bible. The English dictionary says to turn from sin, but that is NOT the Greek meaning in the Bible. The person who repents has simply changed their mind "toward God" (Acts 20:21), acknowledging "the truth" that they are a guilty sinner (Romans 3:19; 2nd Timothy 2:25). Anyone who says repentance means to turn away from sin is perverting the Word of God.
We ought to depart from iniquity because we are saved, not to get saved (2nd Timothy 2:19). But when a believer chooses to sin (and we all do at times), God's grace will much more abound (Romans 5:20).