In context, the word "perfect" in Hebrews 11:39-40 refers to the glorified state of the body in a new heaven and earth.
Here are the Old Testament Saints:
Hebrews 12:22-24
King James Version (KJV)
22 But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels,
23 To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect,
24 And to Jesus the mediator of the new covenant, and to the blood of sprinkling, that speaketh better things than that of Abel.
Let's look at where this word is used elsewhere in Hebrews:
Hebrews 2:10
King James Version (KJV)
10 For it became him, for whom are all things, and by whom are all things, in bringing many sons unto glory, to make the captain of their salvation perfect through sufferings.
Hebrews 5:9
King James Version (KJV)
9 And being made perfect, he became the author of eternal salvation unto all them that obey him;
Hebrews 7:19
King James Version (KJV)
19 For the law made nothing perfect, but the bringing in of a better hope did; by the which we draw nigh unto God.
Hebrews 7:28
King James Version (KJV)
28 For the law maketh men high priests which have infirmity; but the word of the oath, which was since the law, maketh the Son, who is consecrated for evermore.
Hebrews 9:9
King James Version (KJV)
9 Which was a figure for the time then present, in which were offered both gifts and sacrifices, that could not make him that did the service perfect, as pertaining to the conscience;
Hebrews 10:1
King James Version (KJV)
1 For the law having a shadow of good things to come, and not the very image of the things, can never with those sacrifices which they offered year by year continually make the comers thereunto perfect.
Hebrews 10:14
King James Version (KJV)
14 For by one offering he hath perfected for ever them that are sanctified.
Hebrews 11:40
King James Version (KJV)
40 God having provided some better thing for us, that they without us should not be made perfect.
Hebrews 12:23
King James Version (KJV)
23 To the general assembly and church of the firstborn, which are written in heaven, and to God the Judge of all, and to the spirits of just men made perfect,
Just a simple reading of these verses coupled with an understanding of what the word mean will help us to see that in view is the bringing to an end, a completion, of that which the Writer is talking about.
In Chapter Ten, for example, the context deals primarily with Remission of Sins, and his point is that those under Law (and by extension all who offered up sacrifice) were not made complete in regards to sin, but, those that have been sanctified by Christ have been made complete forever in regards to Remission of sins.
We see the transgressions of the Old Testament Saints redeemed by the Blood of Christ here:
Hebrews 9:15
King James Version (KJV)
15 And for this cause he is the mediator of the new testament, that by means of death, for the redemption of the transgressions that were under the first testament, they which are called might receive the promise of eternal inheritance.
The perfection in view has nothing to do with physical resurrection, it refers to being made complete in Christ through New Covenant Realtionship.
Continued...