In the New Testament Christ as the Word of God was incarnated to be a man (John 1:14) to express God, that is, to speak God. Hence, Hebrews 1:2 says that at the last of these days God has spoken to us in the Son. God speaks in both the prophethood and the sonship. The sonship in God's New Testament economy is not only individual but also corporate. God does not have only one son. He did have one Son, the Only Begotten, before the incarnation, but after resurrection, God has many sons. The Only Begotten became the firstborn Son of God, and in the same delivery in resurrection, we all were born, regenerated, to be sons of God (Rom. 8:29; 1 Pet. 1:3). Our big Brother is Christ. We are His followers, His members, His brothers. God's having many sons means that there should be "many speakings." A son of God should speak for God everywhere. When there are no people around, we can speak to the creation (see Mark 16:15). We can say, even to the animals, "My God is my Father, and my big Brother is Christ. He speaks for God. I am His brother, and I do the same thing."
John 15 reveals that Christ is the vine tree and that we are His branches. The branches of the vine tree bear fruit. Today our gospel preaching should be our fruit bearing. We should not try to gain a big crowd in our labor in the gospel. That is the way of Christianity. A big gospel campaign may attract many people, but eventually most of these people are not cared for and become lost. That kind of preaching is like bringing the water out of the well and pouring it on the earth in vain. Instead, we need to be a fruit bearing branch in the way of bearing fruit one by one through the vital groups. God created only one man, but today on the whole earth there are billions of men. This happened by the way of human birth, in a one-by-one way. This is the way to preach the gospel according to the God-ordained way. Christianity dropped God's way and took the way of a big speaker attracting large crowds. The issue of such work is vanity.
As the sons of God, we all need to be those who speak forth Christ. We need to speak to people in a new way with a new language. We may say, "Good morning, sir. I am a son of God, and I would like to speak to you about my God, who is my Father. John 1:12 says that as many as receive Christ, God will give them the authority to become the children of God." This is the right way to preach the gospel. Although the one to whom you are speaking may be too busy to talk at that time, you can make an appointment with him for a later time. All the sons in the divine sonship should speak Christ, and Christ speaks for God.
In the New Testament God speaks in Christ as His firstborn Son (Rom. 8:29), indicating that all the brothers of His firstborn Son as His many sons have to be the word of God speaking for God. They are not only the apostles, the prophets, the evangelists, the shepherds and teachers, etc. (Eph. 4:11), but, even more, they are the sons of God, who are the members of His firstborn Son. They are much higher than the Old Testament prophets.
Today we New Testament believers are God's sons and His prophets. First Corinthians 14:1 says, "Pursue love, and desire earnestly spiritual gifts, but especially that you may prophesy." Verse 31 says, "For you can all prophesy one by one that all may learn and all may be encouraged." As long as you are a son of God, you are also a prophet. As a son you should speak, and as a prophet you should prophesy. You can all prophesy. We need to be prophets to our relatives, colleagues, and classmates. We should prophesy every day and be bubbling over with Christ all the time. Instead of talking to people about the political situation, we should speak something mystical to them. When we speak to someone, perhaps he will say that we are a mental case. But we can tell him, "I'm not a mental case; I'm a case of the son of God." We must learn to be "crazy" to speak for the Lord in this way.