The particular word he uses for “servant” deserves special study. It is therapon. This word is used in the LXX of angels and prophets. There is an ethical character attached to the word. It speaks of service of an affectionate nature, and of a hearty character, performed with care and fidelity. Therapon speaks of service that is of a nobler and a freer character than that of doulos (bondslave). The verb is used of the physician’s care of the sick. Xenophon uses it of the gods taking care of men, and of men worshiping the gods. The use of the word in our present passage is indicative of the close relationship which existed between Jehovah and Moses, and of the fact that his services were of an exceptionally high and important character, and valued by Him.
The fidelity of Moses as a servant in the house of Israel is now said to be a “testimony of those things which were to be spoken after.” The meaning is that the fact that God bore testimony to the fidelity of Moses was a guarantee of the trustworthiness of the report which Moses gave of the things God spoke to him. This interpretation seems to be the correct one in view of the context in Numbers 12:7-8, where God says, “My servant Moses … is faithful in all My house, I will speak to him mouth to mouth, apparently, and not in dark speeches.” — Wuest, page 71.
Christ is Son over His house, the one in which Moses was a servant, so, even though Moses was faithful, Christ is better.
house (v.5) — Israel
house (v.6) — all those who believe
hold fast (v.6) = “holding one’s course toward” — like a ship holding its course toward its destination
confidence (v.6) — boldness and freedom of speech
rejoicing (v.6) — only genuine confidence produces joy
I don’t agree with Wuest’s take on this passage, but I’m including it here to show what appears to be the most common understanding.
Now, the writer, keeping in mind the fact that only part of his readers were really saved, and the other part were merely making a profession of salvation, and the latter under stress of persecution were in danger of relapsing back to apostate Judaism, proposes to these readers a test whereby they can tell whether they really belong to the house of God or not, that is, whether they are really saved or not. The “if” in the Greek text is the particle ean, introducing a future, unfulfilled, hypothetical condition. The writer is proposing a condition as yet unfulfilled. If these Jews, to whom he is writing hold fast their confidence and the rejoicing of their professed hope in Messiah firm to the end of their lives, that fact shows that they belong to the house of God, in other words, are saved. If they do not do so, but instead, renounce that profession and return to the abrogated system of Levitical sacrifices, that shows that they never were saved. It is not the retention of salvation that is in question here, but the possession of salvation. The text does not say, whose house will we continue to be,” but “whose house are we.” Frequently the verb of being is left out by the Greek writer, it being understood in the light of the context. But it is in the Greek text here, and in the present tense. Therefore, the subject of the security of the believer is not in view here.
This verse must be understood in the light of its historical background and context. The purpose of the writing of the Epistle to the Hebrews was to meet a certain condition in the first century. It was to reach Jews who had outwardly left the temple sacrifices, had identified themselves with the visible Christian Church, had made a profession of Messiah as High Priest, and who were at the time suffering persecution from apostate Judaism in an effort to force them to renounce their professed faith in Messiah and return to the First Testament sacrifices. Now — if under the pressure of this persecution they should hold fast their confidence and rejoicing of their hope in Messiah to the end of their lives, that would show that they were saved, and if not, that would indicate that they had never been saved. This verse therefore cannot be made to refer in a secondary application to the present day, since the conditions in the first century which the verse was written to meet, do not obtain today. — Wuest, pages 72-73.