As Jesus traveled around ministering with His disciples, He performed many miracles, signs, and wonders. These signs were evidence of His divine authority, causing many to believe His message and respond to Him in faith. But the Pharisees, who also witnessed these signs, were filled with wickedness and unbelief, and they “plotted how they might kill Jesus” (Matthew 12:14). When they asked Jesus for a sign to prove He was the Messiah, the Lord saw beyond their words into their treacherous, faithless hearts. Jesus responded, “An evil and adulterous generation seeks for a sign, but no sign will be given to it except the sign of the prophet Jonah” (Matthew 12:39, ESV).
A similar exchange took place in Matthew 16:1–4. The Pharisees and Sadducees came to test Jesus, “demanding that he show them a miraculous sign from heaven to prove his authority” (verse 1, NLT). Again, Jesus confronted their unbelief, noting that they could interpret meteorological signs, but not “the signs of the times. An evil and adulterous generation seeks for a sign, but no sign will be given to it except the sign of Jonah” (Matthew 16:2–4, ESV).
The “sign of Jonah” is a reference to Jesus Christ’s death, burial, and resurrection (see Matthew 12:40; cf. Jonah 1:17). The religious leaders already had more than enough proof of Jesus Christ’s identity. They knew the messianic prophecies Christ was fulfilling. They had seen with their own eyes His miracles of healing and exorcisms. What more could He do if these signs weren’t indisputable evidence enough? Nothing, concluded Jesus. The fact that they continued seeking a sign demonstrated the hardness of their unbelieving hearts. The only definitive sign they might accept to validate Christ’s authority would be His triumph over death on the cross (Romans 6:9; 2 Timothy 1:10). The Pharisees probably did not comprehend what Jesus meant just then, but they might have remembered and understood His words after the resurrection.
Scripture teaches that it’s wise to test the legitimacy of a person who claims to be God’s prophet (1 John 4:1). Jesus wasn’t saying that it is evil or wrong to seek for a sign. God gave signs to Moses (Exodus 4:1–9) and Gideon (Judges 6:11–22) to validate His Word. He urged King Ahaz, “Ask the Lord your God for a sign, whether in the deepest depths or in the highest heights” (Isaiah 7:11; see also Isaiah 7:10–25). Miraculous signs are sometimes the catalyst to spark a person’s faith and trust in Jesus (see John 2:23; 11:45). God gives signs to help those struggling to believe (John 4:43–54).
The purpose of a divine sign is always to lead people to respond to God’s message in faith. The scribes and Pharisees asked for a sign to trick Jesus and ultimately destroy Him. For this reason, Jesus said to them, “An evil and adulterous generation seeks for a sign.” He perceived the rebellion and unbelief in their hearts. Moreover, Jesus recognized these men as spokespersons for an entire generation of unfaithful, unbelieving people.
The term adulterous generation refers to the Old Testament concept that adultery or sexual infidelity, in a spiritual sense, is equivalent to apostasy or idolatry (see Jeremiah 3:20; Isaiah 57:3; Ezekiel 16:32; Hosea 1—3). Jesus said, “If anyone is ashamed of me and my words in this adulterous and sinful generation, the Son of Man will be ashamed of them when he comes in his Father’s glory with the holy angels” (Mark 8:38). James wrote, “You adulterers! Don’t you realize that friendship with the world makes you an enemy of God? I say it again: If you want to be a friend of the world, you make yourself an enemy of God” (James 4:4, NLT). God considers His spiritual union with His people to be as intimate and exclusive as the bond between a husband and wife (see Ezekiel 16:8; Isaiah 54:5; Jeremiah 3:14; 31:32; Ephesians 5:31–32).
Believing people with faithful hearts may indeed be given a sign from God—to confirm His Word (Hebrews 2:3–4; Mark 16:20); to assure them of His presence (Exodus 3:1–5); to demonstrate His power (Jeremiah 32:21); to warn against rebellion (Numbers 17:10; 1 Samuel 2:34); and to encourage them (Deuteronomy 7:17–19; Matthew 2:9–10). The insincere unbelievers of “an evil and adulterous generation” in Jesus’ day sought for a sign, but none was given to it except the death, burial, and resurrection of Jesus Christ.