The link between the Old and New Testaments of the Bible is sometimes difficult to grasp because of the differences between the Old and New Covenants that govern their content. The Old Covenant was “made with Israel as the descendants of Abraham, Isaac and Jacob and as the people the Lord has redeemed from bondage to an earthly power.” It was “a conditional divine pledge to be Israel’s God (as her Protector and the Guarantor of her blessed destiny); the condition: Israel’s total consecration to the Lord as his people (His kingdom) who live by his rule and serve his purposes in history” (Major Covenants in the Old Testament, p. 16, KJSB). The Mosaic Law was given to the Israelites so that they would be aware of and follow the standard by which God would measure their devotion and obedience to him. At the end of his life, Moses told the people of Israel, “For the commandment that I command you today is not too hard for you, neither is it far off. It is not in heaven, that you should say, ‘Who will ascend to heaven for us and bring it to us, that we may hear it and do it? Neither is it beyond the seas that you should say, ‘Who will go over the sea for us and bring it to us, that we may hear it and do it? But the word is very near you. It is in your mouth and in your heart so that you can do it” (Deuteronomy 30:11-14). The Old Testament ends with God rebuking Israel’s priests for turning aside from the way that he had established for them to worship him (Malachi 2:8), and a declaration that Judah had profaned God’s covenant by marrying the daughter of a foreign god (Malachi 2:11). God announced his intention of establishing a new covenant through the prophet Malachi. God said, “Behold, I send my messenger, and he will prepare the way before me. And the Lord whom you seek will suddenly come to his temple; and the messenger of the covenant in whom you delight, behold he is coming says the LORD of hosts” (Malachi 3:1)

The New Covenant was “an unconditional divine promise to unfaithful Israel to forgive her sins and establish a relationship with her on a new basis by writing His law ‘in their hearts’—a covenant of pure grace” (Major Covenants in the Old Testament, p. 16, KJSB). Grace was not a new concept to the people of Israel, but they didn’t seem to understand how it worked. Jesus talked about grace in terms of a “benefit” or “credit” that one might receive for doing a good deed (Luke 6:32-34), and then said, “But love your enemies, and do good, and lend, expecting nothing in return, and your reward will be great, and you will be sons of the Most High, for he is kind to the ungrateful and the evil. Be merciful, even as your Father is merciful” (Luke 6:35-36). The Apostle Paul told the believers in Ephesus that it is “by grace that you have been saved…For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast” (Ephesians 2:5, 8-9). The Greek word that is translated works in Ephesians 2:9, er-gon (erˊ-gon) is speaking “of works of the law, meaning works required or conformable to the Mosaic moral law and required by the law” (G2041). Paul indicated that a person might be inclined to boast if he was able to live according to the Mosaic Law. Therefore, God chose to give salvation to us based on our faith in Jesus Christ.

God said of his messenger in Malachi 3:1, “he will prepare the way before me.” The Hebrew word derek (dehˊ-rek) is used figuratively to refer to “a course of life or mode of (action)” (H1870). When God said that his messenger would prepare the way, he meant that his messenger would focus people’s attention on the way they were living. Zechariah’s prophecy about his son John touched on this very point (Luke 1:76), and indicated that John would, “give knowledge of salvation to his people in the forgiveness of sins because of the tender mercy of our God, whereby the sunrise shall visit us from on high to give light to those who sit in darkness and in the shadow of death, to guide our feet into the way of peace” (Luke 1:77-79). The idea that God’s grace can guide our feet into the way of peace is based on the fact that the Holy Spirit is able to convict us of our sin and cause us to repent (John 16:8). It says in Matthew 3:1-3:

In those days John the Baptist came preaching in the wilderness of Judea, “Repent, for the kingdom of heaven is at hand.” For this is he who was spoken of by the prophet Isaiah when he said,

“The voice of one crying in the wilderness:
‘Prepare the way of the Lord;
    make his paths straight.’”

The Greek word that is translated repent in Matthew 3:1, metanoeo (met-an-o-ehˊ-o) means “to think differently or afterwards, i.e. reconsider” (G3340) and has to do with changing your mind. Paul describes repentance as a time-limited, opportunity in Hebrews 12:17 where he says of Jacob’s brother Esau, “For you know that afterward, when he desired to inherit the blessing, he was rejected, for he found no chance to repent, though he sought it with tears.” John the Baptist’s preparation of the way for those who wanted to receive Christ as their Savior was also a time-limited opportunity. Not long after Jesus launched his ministry, John was arrested (Matthew 4:12), and a short while later, he was beheaded by Herod the tetrarch (Matthew 14:10). Jesus said of John, “Truly, I say to you, among those born of women there has arisen no one greater than John the Baptist. Yet the one who is least in the kingdom of heaven is greater than he” (Matthew 11:11).

Jesus’ declaration that the one who is least in the kingdom of heaven is greater than John the Baptist (Matthew 11:11) was based on the fact that John was not a born again believer. Jesus prefaced his statement about John with the stipulation “among those born of women.” Jesus explained to a man named Nicodemus that “unless one is born of water and the Spirit, he cannot enter the kingdom of God. That which is born of flesh is flesh, and that which is born of the Spirit is spirit” (John 3:5-6). Jesus distinguished between the two types of birth that a person could experience and stated that a spiritual birth was required for entrance into God’s kingdom. Throughout the New Testament, the Greek word that was used to refer to John as God’s messenger, aggelos (angˊ-el-os) is translated as angel or angels. Aggelos is derived from the word ago (agˊ-o), which is used metaphorically in Romans 2:4 to refer to leading (ago) someone to repentance. Paul asked, “Or do you presume on the riches of his kindness and forbearance and patience, not knowing that God’s kindness is meant to lead you to repentance?” It seems likely that God’s messenger, John the Baptist was perceived by most people to be an angel of kindness. John brought hope to those who were sitting in darkness and in the shadow of death through his message about God’s forgiveness of sins. It was the religious hypocrites who hated John and wanted to stop him from leading people to the light of Jesus Christ.

Jesus’ parable about tenants who killed their master’s son so that they could have his inheritance explains the reason why God replaced the Old Covenant that he made with Abraham’s descendants with a new one. Jesus stated:

“Hear another parable. There was a master of a house who planted a vineyard and put a fence around it and dug a winepress in it and built a tower and leased it to tenants, and went into another country. When the season for fruit drew near, he sent his servants to the tenants to get his fruit. And the tenants took his servants and beat one, killed another, and stoned another. Again he sent other servants, more than the first. And they did the same to them. Finally he sent his son to them, saying, ‘They will respect my son.’ But when the tenants saw the son, they said to themselves, ‘This is the heir. Come, let us kill him and have his inheritance.’ And they took him and threw him out of the vineyard and killed him. When therefore the owner of the vineyard comes, what will he do to those tenants?” They said to him, “He will put those wretches to a miserable death and let out the vineyard to other tenants who will give him the fruits in their seasons.”

Jesus said to them, “Have you never read in the Scriptures:

“‘The stone that the builders rejected
    has become the cornerstone;
this was the Lord’s doing,
    and it is marvelous in our eyes’?

Therefore I tell you, the kingdom of God will be taken away from you and given to a people producing its fruits. And the one who falls on this stone will be broken to pieces; and when it falls on anyone, it will crush him.” (Matthew 21:33-44)

The issue that caused a conflict between the master of the house and his tenants was possession of the fruit from his vineyard. When the master’s servants came to get his fruit, the tenants “beat one, killed another, and stoned another” (Matthew 21:35). What we’re not told is whether or not there was any fruit, and if there was, what the tenants did with it. Jesus’ solution seems to indicate that the tenants hadn’t produced any fruit. Jesus said the kingdom of God would be taken away and given to a people producing or bringing forth its fruits (Matthew 21:43).

Jesus talked about bringing forth fruit in many of his lessons and parables and explained in his parable of the sower that it’s not just hearing the word of God, but understanding it that causes fruit to be produced in the heart of a believer (Matthew 13:23). Jesus said understanding with the heart causes a person to be converted (Matthew 13:15). To be converted means that you reverse your direction in life and “become another kind of person e.g., to become like children” (G4762). Jesus told his disciples, “Unless you turn (strepho, G4762) and become like children, you will never enter the kingdom of heaven” (Matthew 18:3). The first step in the process of being converted is to repent. John the Baptist told the people who came to him when he was preaching in the wilderness of Judea, “Repent, for the kingdom of heaven is at hand.” (Matthew 3:1-2) and later, Jesus told the religious hypocrites who wanted to see a sign from him, “The men of Ninevah will rise up at the judgment with this generation and condemn it, for they repented at the preaching of Jonah, and behold something greater than Jonah is here” (Matthew 12:41).