JESUS THE APOSTLE
Hebrews 3.1
"Jesus the Apostle and High Priest." Jesus as the High Priest very well understood, but Jesus the Apostle? This may be explained in this way, the Jesus is the Apostle of His Father GOD as the First among the all the first (Colossians 1.15.17-18). Jesus was the First Born before all the creation, and so, He is the First among and Apostles, Teaches, Preachers, Kings, Leaders, Authorities, Saviors, and gods. He is the First on Whom the Name of GOD is rests, and the First and only Reflection of the Image and Representation of the GOD, His Father. Jesus also First in Resurrection from the dead, First and only Savior of humanity from death, and the First Giver if Eternal Life. Jesus also the very First Who gave the Law of GOD to people, and the First Teacher of the Word of GOD. As it is said in many passages of the Bible, Jesus Christ is First in everything, and so, as the Authority appointed by His Father GOD over all His creation, Jesus rightfully can be the First Apostle of His GOD Father as the true and legitimate Authority of all believers in GOD and their churches.
The 12 followers of Christ are also Apostles, but they are Apostles of Christ and the people whom they teach. In Ephesians 4.11 Paul talking about Gifts of GOD what He is giving to His followers, and He had made some of His followers as Apostles. Does Paul talking here only about 12 Apostle of Christ, or he is talking here about other believers and faithful who are also appointed by Jesus Christ as Apostles? It is very possible.
So, conclusion can be made as such, that Jesus Christ is the Apostle appointed by His GOD Father, and the first 12 followers of Jesus, Jesus appointed as His Apostles, to do the same work as He does, propagate the Gospel all over the world. It is also possible that Jesus Christ could appoint and other Apostles beside His 12, according to Ephesians 4.11.
THE BUILDER OF THE HOUSE
Hebrews 3.2-5
Very interesting comparison Paul made between Jesus Christ and Moses. Jesus and Moses both were appointed over GOD'S house (Number12.7). GOD'S house mean the people of GOD - Israelites, according to the Old Covenant, and the rest of the world according to a New Covenant. Both are faithful and worthy Overseers of the house of GOD (1-2). Of course, the Builder of the house Jesus has more glory than Moses (3), because He is not a human, He is GOD because He is the Son of GOD and build everything according to His Father's instructions.
But the true Source and the Builder of the house of Israel and the house of all believers in GOD (the world) and of all the things, is GOD Father (4). The GOD Father created and made everything through His Faithful Son Jesus Christ (John 1.3) (1Corinthians 8.6) (Colossian 1.16-17) (Hebrews 1.2).
GOD'S REST
Hebrews 3.11.18
Where is the Rest of GOD? The Rest of GOD is His Kingdom, His Spiritual World, in which the souls of all the faithful to GOD will Rest for eternity with their GOD, as their final Sabbath.
In the next chapter 4, Paul made emphasis on the Sabbath Day in relation to Rest of GOD, because Saturday Day is the Rest Day, on which GOD Rested from all His works and Commanded His people, Israelites and Gentiles who lived among them, to do the same, to rest on the Seventh Sabbath Day, just as GOD Himself rested on that Holy Day that He has blessed and Sanctified. But because GOD rested from all His works long before He had issued His Command to His people to Rest on the Seventh Day as He does, in this matter the Sabbath became the Universal Day of the Rest for whole humanity.
All Gentiles who lived in Israel in Biblical times, required to obey the Sabbath Day together with all other Holidays prescribed to Israel by their GOD. This is also means that Gentiles, if they want to be blessed, sanctified, and be holy, and receive their Forgiveness and Salvation from GOD, they must also obey the Sabbath Day as all native Jews do.
Is this requirement of the Sabbath relating only to those Gentiles who live in Israel? Not at all. Because if Gentile believe and follow the GOD of Israel (the GOD Father and His Son Jesus Christ), then the GOD'S Law concerning Sabbath applies to all Gentiles of the world without any exceptions, no matter where Gentiles live, in Israel or not.
The Sabbath Paul specified as the Place of the Rest of GOD, this also means (figuratively) that the Sabbath is the Kingdom, and the Kingdom of GOD is the Sabbath for all those who will rest from their worries and labor, and enjoy true rest, happiness, and joy, forever.
So, the point is that beside many other Requirements, Laws, and Regulations of GOD concerning Forgiveness of sins and Salvation of the souls of human beings, the Sabbath Day is also one of those Requirements and Laws (Hebrews 4.3-6.9-11) that directly connected to GOD'S most important Ordinances and Commandments.
~ Rest of GOD: (Psalm 95.8-11) (Numbers 14.29-35) (Hebrews 3.11.18, 4.3-6.9-11).