Answer
“Stubborn as a mule” is a well-known idiom. The Bible actually mentions mules in relation to their stubbornness in Psalm 32:9: “Do not be like the horse or the mule, which have no understanding but must be controlled by bit and bridle.” When it comes to following God’s commands, we should not be stubborn or obstinate or intractable. We must not turn our heads away and “stiffen the neck.” We must learn to yield and be pliable in His hands. It’s not our wish for God to use the bit and bridle on us.
The Bible records instances of stubborn, mule-like behavior of human beings on occasion. In the Old Testament, Pharaoh was famously stubborn (Exodus 7:13–14), but his recalcitrance did himself and his nation no good. But stubbornness was also displayed later by the nation of Israel, God’s chosen people, who rebelled against God over and over, turning away from His love and protection. In fact, the Hebrew word translated “stubborn” means “turned away, morally obstinate, rebellious, and backsliding.”
The Old Testament relates the sad history of the Jews who stubbornly turned their backs on God, forgot His works, disobeyed His laws, and followed strange gods. In Deuteronomy 9, Moses recounts Israel’s stubbornness concerning the golden calf they made at Mount Sinai. At that time God had told Moses, “I have seen this people, and behold, it is a stubborn people” (Deuteronomy 9:13, ESV). God’s anger was so great that He had considered destroying the people completely for their stubborn, stiff-necked ways (verse 14).
God considers stubbornness so great a sin that He included what seems today to be an overly harsh punishment for a stubborn and rebellious son. If a son refused to obey his parents, would not respond to discipline, and led a dissolute life, the parents were to bring him to the elders of his city and “all the men of his town are to stone him to death. You must purge the evil from among you. All Israel will hear of it and be afraid” (Deuteronomy 21:21). Stubbornness and defiance of God and His ordained authority is a serious offense, one that can spread like poison throughout a community. The Mosaic Law against stubbornness was designed to stop that spread.
In the New Testament, we see more examples of stubbornness. When Jesus healed a man with a withered hand on the Sabbath, the Pharisees’ hardness of heart grieved and angered Jesus. Instead of praising the Lord for His healing power and acknowledging their Messiah, the Pharisees’ rebellious hearts caused them to try to kill Him (Mark 3:1–6). As Stephen was closing his speech before the Sanhedrin, he upbraided them for their foolhardy stubbornness: “You stiff-necked people! Your hearts and ears are still uncircumcised. You are just like your ancestors: You always resist the Holy Spirit!” (Acts 7:51).
When Paul preached to the Jews in Corinth, they continued to reject the message of salvation through Jesus Christ. For three months Paul reasoned with them in their synagogue, but “some of them became obstinate; they refused to believe and publicly maligned the Way” (Acts 19:9). As a result, Paul took the disciples and left the rejecters of the good news in their stubbornness and unbelief.
Unfortunately, this is the fate that awaits all those who persist in rejecting Christ. God will eventually turn them over to the hardness of their hearts and no longer plead with them. The sad result of such mulish obstinance is made clear in Romans 2:5: “Because of your stubbornness and your unrepentant heart, you are storing up wrath against yourself for the day of God’s wrath, when his righteous judgment will be revealed.”