Jesus Christ is our source for authority today. Jesus said, "All authority has been given to Me in heaven and on earth" (Matthew 28:18).
However, none living today has ever seen Jesus. Also, despite claims to the contrary, Jesus does not speak to us directly today. So, how is it we are to know the will of Jesus? He is the authority, so how are we to know what he authorizes?
The New Covenant
First, note that the New Testament is the will of Jesus. Numerous passages establish this fact. For example, notice that the writer of Hebrews states that Jesus is the mediator of a New Testament, which is contrasted to the Old Law. "And for this reason He is the Mediator of the new covenant, by means of death, for the redemption of the transgressions under the first covenant, that those who are called may receive the promise of the eternal inheritance. For where there is a testament, there must also of necessity be the death of the testator. For a testament is in force after men are dead, since it has no power at all while the testator lives" (Hebrews 9:15-17). When Christ died on the cross, he initiated a new law into being.
When the New Testament was ratified by the blood of Jesus, the Old Law was taken away (cf. Heb. 10:9-10; Eph. 2:14-17; Col. 2:14-17). Paul said, "Therefore the law was our tutor to bring us to Christ, that we might be justified by faith. But after faith has come, we are no longer under a tutor" (Galatians 3:24-25). Hence, we must not look to the Old Law (Old Testament, in its ordinances and commandments) as our authority today. We are no longer under the tutor.
Jesus is the source of all authority, but it is inaccurate to say that all we must do is look at the words of Jesus. Jesus chose to utilize his servants the apostles to speak through them His will. Paul said, "Now then, we are ambassadors for Christ, as though God were pleading through us: we implore you on Christ’s behalf, be reconciled to God" (2 Corinthians 5:20). This certainly agrees with Jesus’ statement in John 16:13, "However, when He, the Spirit of truth, has come, He will guide you into all truth; for He will not speak on His own authority, but whatever He hears He will speak; and He will tell you things to come." When the apostles’ speak, they do so by the authority of Jesus Christ. To hear them is to hear Christ. To reject the apostles’ doctrine, (cf. Acts 2:42) is to reject inspiration, and Christ Himself.
As the apostles, and other inspired men, wrote down the words of Jesus and teaching of the Spirit, they made known God’s will for man today. "God, who at various times and in various ways spoke in time past to the fathers by the prophets, has in these last days spoken to us by His Son, whom He has appointed heir of all things, through whom also He made the worlds" (Hebrews 1:1-2). These writings are known as the New Testament. We are to accept the New Testament as God’s will to man today.
Some facts about the New Testament:
It is a divine message, the word of God. "For this reason we also thank God without ceasing, because when you received the word of God which you heard from us, you welcomed it not as the word of men, but as it is in truth, the word of God, which also effectively works in you who believe" (1 Thessalonians 2:13).
It is a complete message, giving man everything he needs. "All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God may be complete, thoroughly equipped for every good work" (2 Timothy 3:16-17).
It is the final message. "Beloved, while I was very diligent to write to you concerning our common salvation, I found it necessary to write to you exhorting you to contend earnestly for the faith which was once for all delivered to the saints" (Jude 3).
Jesus, the source of divine authority today, speaks through the New Testament. To be His follower, we must obey His word! Everything that we teach or practice as children of God must find its authorization in the pages of the New Testament.
