Letter or epistle to the Hebrews or simply To Hebrews. There is no evidence that the title needs the Apostle Paul’s name in it as the King James Versions does.
Most today will say "do not know" based on points of syntax or the rigid clarity (for Paul was known to go off on tangents in some of his letters) ,. The ancient and not so ancient view is that the Apostle Paul was the author:
Because the purpose of the letter was different to other of Paul the omission of certain elements of the doctrine is no reason to discard Paul as the author eg. The letter does not speak of:
The letter is anonymous because Paul was so universally hated by the Jews, hence, to prevent prejudice, he writes it with his special mark - see 2 Thessalonians (my opinion).
The key verse being:
Wherefore coming into the world he says, Sacrifice and offering thou willedst not; but thou hast prepared me a body. Thou tookest no pleasure in burnt-offerings and sacrifices for sin. Then I said, Lo, I come (in the roll of the book it is written of me) to do, O God, thy will. (Hebrews 10:5-7 Darby)
Certainly written before 70AD, perhaps in AD 61-63 .
Written from Italy ( Rome) to the Jews or Hebrew Christians living most likely in Jerusalem.
Christian Jews based on the title, having no manuscript without this title .
May also mean Hebrew speaking people, but the tenet is definitely Jewish with a presumption of an understanding of the Law – see 5:12, 10:25
Jesus Christ: the superiority of Christ’s person (1:1 to 4:13)
Jesus Christ: the superiority of Christ’s work ( 4:14 to 10:18)
The Christian ( 10:19 to 13:25).
It specifically mimics Leviticus – the Levitical law - showing the superiority of the priesthood of Christ – being after the order of Melchizedek – as compared with that of Aaron.
1. Christ, the Son of God and His Glory (1:1 to 2:4)
2. Christ, the Son of Man, His glory and His salvation (2:5 to 4:13)
3. Christ as priest in the heavenly Sanctuary (4:14 – 10)
4. Instructions to Christians and exhortationsPrincipal or Key Verses
1 God, who at various times and in various ways spoke in time past to the fathers by the prophets, 2 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; 3 who being the brightness of His glory and the express image of His person, and upholding all things by the word of His power, when He had by Himself purged our sins, sat down at the right hand of the Majesty on high, 4 having become so much better than the angels, as He has by inheritance obtained a more excellent name than they.
We must pay more careful attention, therefore, to what we have heard, so that we do not drift away.
But we see Jesus, who was made a little lower than the angels for the suffering of death, crowned with glory and honour; that he by the grace of God should taste death for every man.
Therefore, in all things He had to be made like His brethren, that He might be a merciful and faithful High Priest in things pertaining to God, to make propitiation for the sins of the people.
For the word of God is quick [living], and powerful, and sharper than any two-edged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart.
For we do not have a High Priest who cannot sympathize with our weaknesses, but was in all points tempted as we are, yet without sin.
Though he were a Son, yet learned he obedience by the things which he suffered;
And we desire that every one of you do show the same diligence to the full assurance of hope unto the end:
Therefore He is also able to save to the uttermost those who come to God through Him, since He always lives to make intercession for them.
Now this is the main point of the things we are saying: We have such a High Priest, who is seated at the right hand of the throne of the Majesty in the heavens,
But Christ came as High Priest of the good things to come, with the greater and more perfect tabernacle not made with hands, that is, not of this creation.
so Christ was offered once to bear the sins of many. To those who eagerly wait for Him He will appear a second time, apart from sin, for salvation.
And every priest standeth daily ministering and offering oftentimes the same sacrifices, which can never take away sins: 12 But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God;
But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.
Therefore we also, since we are surrounded by so great a cloud of witnesses, let us lay aside every weight, and the sin which so easily ensnares us, and let us run with endurance the race that is set before us, 2 looking unto Jesus, the author and finisher of our faith, who for the joy that was set before Him endured the cross, despising the shame, and has sat down at the right hand of the throne of God.
Let brotherly love continue…
The book has seven ideas:
The old and new are contrasted, with the perfectness of Christ emphasised. This he does with the emphasis on the Heavenlies (15 times) – noting that the Law emphasised the earthly.
Comparison is made of Christ and his work to angels, Moses, Aaron (The High Priest who could not sit down) and The Law (Noting that chapter 11 is for exhortation). Compare this with the mount of transfiguration – Christ is compared with Moses (ie the Law) and the Elijah (the Prophets) but these were to be superseded by Christ ( This is my beloved Son, in whom I am well pleased; hear ye him).
Chapter 1 1God, who at various times and in various ways spoke in time past to the fathers by the prophets, 2has 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; 3who being the brightness of His glory and the express image of His person, and upholding all things by the word of His power, when He had by Himself purged our sins, sat down at the right hand of the Majesty on high, 4having become so much better than the angels, as He has by inheritance obtained a more excellent name than they.
Chapter 2:9 (KJV) 9But we see Jesus, who was made a little lower than the angels for the suffering of death, crowned with glory and honour; that he by the grace of God should taste death for every man.
Chapter 10:12 (KJV) But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God;
 Halley, Halley’s Bible Handbook, Zondervan, 1969
 Gaebelein, Concise Commentary, Loizeaux Brothers, 1985.
 Donald Guthrie, Hebrews, Intervarsity, 1983.
 "If in this book you choose to look Five things observe with care
Of whom it speaks,
To whom it speaks
Why and When and Where"
 NIV uses ‘superior’
NIV = The Holy Bible, New International Version Original work copyright 1973, 1978, 1984 by International Bible Society.
NKJV=The Holy Bible, New King James Version Original work copyright © 1979, 1980, 1982 by Thomas Nelson, Inc.
KJV=The Holy Bible, King James Version. This book is not copy protected.