This is for several OT verses referred to in Hebrews:
In Hebrew 1 the writer is quoting Psalms 2.7 and 2 Samuel 7:14
Hebrews 1:5 For unto which of the angels said he at any time, Thou art my Son, this day have I begotten thee? And again, I will be to him a Father, and he shall be to me a Son?
Psalms 2:7 declaring the ordinance of the Lord: the Lord said to me, Thou art my Son, to-day have I begotten thee.
2 Samuel 7:14 I will be to him a father, and he shall be to me a son. And when he happens to transgress, then will I chasten him with the rod of men, and with the stripes of the sons of men.
Hebrews 1:7
And of the angels he saith, Who maketh his angels spirits, and his ministers a flame of fire.
Psalms 103:4
Who makes his angels spirits, and his ministers a flaming fire.
Hebrews 1:8,9
But unto the Son [he saith], Thy throne, O God, [is] for ever and ever: a sceptre of righteousness [is] the sceptre of thy kingdom. Thou hast loved righteousness, and hated iniquity; therefore God, [even] thy God, hath anointed thee with the oil of gladness above thy fellows.
Psalms 44:6,7
Thy throne, O God, is for ever and ever: the sceptre of thy kingdom is a sceptre of righteousness. Thou hast loved righteousness, and hated iniquity: therefore God, thy God, has anointed thee with the oil of gladness beyond thy fellows.
Hebrews 1:10-12
And, Thou, Lord, in the beginning hast laid the foundation of the earth; and the heavens are the works of thine hands: They shall perish; but thou remainest; and they all shall wax old as doth a garment; And as a vesture shalt thou fold them up, and they shall be changed: but thou art the same, and thy years shall not fail.
Psalms 101:25-28 In the beginning thou, O Lord, didst lay the foundation of the earth; and the heavens are the works of thine hands. They shall perish, but thou remainest: and they all shall wax old as a garment; and as a vesture shalt thou fold them, and they shall be changed. But thou art the same, and thy years shall not fail.
Hebrews 2:12
Saying, I will declare thy name unto my brethren, in the midst of the church will I sing praise unto thee.
Psalms 21:22 I will declare thy name to my brethren: in the midst of the church will I sing praise to thee.
Hebrews 2:13
And again, I will put my trust in him. And again, Behold I and the children which God hath given me.
2 Samuel 22:3 my God; he shall be to me my guard, I will trust in him: he is my protector, and the horn of my salvation, my helper, and my sure refuge; thou shalt save me from the unjust man.
Hebrews 3:7-11 Wherefore (as the Holy Ghost saith, To day if ye will hear his voice, Harden not your hearts, as in the provocation, in the day of temptation in the wilderness: When your fathers tempted me, proved me, and saw my works forty years. Wherefore I was grieved with that generation, and said, They do alway err in [their] heart; and they have not known my ways. So I sware in my wrath, They shall not enter into my rest.)
Hebrews 3:15 While it is said, To day if ye will hear his voice, harden not your hearts, as in the provocation.
Hebrews 4:3 For we which have believed do enter into rest, as he said, As I have sworn in my wrath, if they shall enter into my rest:
Hebrews 4:5 And in this [place] again, If they shall enter into my rest.
Hebrews 4:7 Again, he limiteth a certain day, saying in David, To day, after so long a time; as it is said, To day if ye will hear his voice, harden not your hearts.
Psalms 94:7-11 For he is our God; and we are the people of his pasture, and the sheep of his hand. Today if ye will hear his voice, harden not your hearts, as in the provocation, according to the day of irritation in the wilderness: where your fathers tempted me, proved me, and saw my works. Forty years was I grieved with this generation, and said, They do always err in their heart, and they have not known my ways. So I sware in my wrath, They shall not enter into my rest.
Hebrews 8:5
Who serve unto the example and shadow of heavenly things, as Moses was admonished of God when he was about to make the tabernacle: for, See, saith he, [that] thou make all things according to the pattern shewed to thee in the mount.
Exodus 25:40
See, thou shalt make them according to the pattern shewed thee in the mount.
Hebrews 9:19,20 For when Moses had spoken every precept to all the people according to the law, he took the blood of calves and of goats, with water, and scarlet wool, and hyssop, and sprinkled both the book, and all the people, saying, This [is] the blood of the testament which God hath enjoined unto you.
Exodus 24:8 And Moses took the blood and sprinkled it upon the people, and said, Behold the blood of the covenant, which the Lord has made with you concerning all these words.
Hebrews 10:16,17 This [is] the covenant that I will make with them after those days, saith the Lord, I will put my laws into their hearts, and in their minds will I write them; And their sins and iniquities will I remember no more.
Jeremiah 38:31-34
Behold, the days come, saith the Lord, when I will make a new covenant with the house of Israel, and with the house of Juda: not according to the covenant which I made with their fathers in the day when I took hold of their hand to bring them out of the land of Egypt; for they abode not in my covenant, and I disregarded them, saith the Lord. For this is my covenant which I will make with the house of Israel; after those days, saith the Lord, I will surely put my laws into their mind, and write them on their hearts; and I will be to them a God, and they shall be to me a people. And they shall not at all teach every one his fellow citizen, and every one his brother, saying, Know the Lord: for all shall know me, from the least of them to the greatest of them: for I will be merciful to their iniquities, and their sins I will remember no more.
Hebrews 10:30
For we know him that hath said, Vengeance [belongeth] unto me, I will recompense, saith the Lord. And again, The Lord shall judge his people.
Deuteronomy 32:36
or the Lord shall judge his people, and shall be comforted over his servants; for he saw that they were utterly weakened, and failed in the hostile invasion, and were become feeble:
Hebrews 11:5 By faith Enoch was translated that he should not see death; and was not found, because God had translated him: for before his translation he had this testimony, that he pleased God
Genesis 5:24 And Enoch was well-pleasing to God, and was not found, because God translated him
Hebrews 12:5,6 And ye have forgotten the exhortation which speaketh unto you as unto children, My son, despise not thou the chastening of the Lord, nor faint when thou art rebuked of him: For whom the Lord loveth he chasteneth, and scourgeth every son whom he receiveth.
Proverbs 3:11,12 My son, despise not the chastening of the Lord; nor faint when thou art rebuked of him: for whom the Lord loves, he rebukes, and scourges every son whom he receives.
Hebrews 12:12 Wherefore lift up the hands which hang down, and the feeble knees;
Isaiah 35:3 Be strong, ye relaxed hands and palsied knees.
Hebrews 12:20 (For they could not endure that which was commanded, And if so much as a beast touch the mountain, it shall be stoned, or thrust through with a dart:
Exodus 19:13 A hand shall not touch it, for every one that touches shall be stoned with stones or shot through with a dart, whether beast or whether man, it shall not live: when the voices and trumpets and cloud depart from off the mountain, they shall come up on the mountain.
Hebrews 12:21 And so terrible was the sight, [that] Moses said, I exceedingly fear and quake:)
Deuteronomy 9:19 And I was greatly terrified because of the wrath and anger, because the Lord was provoked with you utterly to destroy you; yet the Lord hearkened to me at this time also.
Hebrews 12:26 Whose voice then shook the earth: but now he hath promised, saying, Yet once more I shake not the earth only, but also heaven.
Haggai 2:7 For thus saith the Lord Almighty; Yet once I will shake the heaven, and the earth, and the sea, and the dry land;
Hebrews 12:29 For our God [is] a consuming fire.
Deuteronomy 4:24 For the Lord thy God is a consuming fire, a jealous God.
Hebrews 13:5 [Let your] conversation [be] without covetousness; [and be] content with such things as ye have: for he hath said, I will never leave thee, nor forsake thee.
Deuteronomy 31:6 Be courageous and strong, fear not, neither be cowardly, neither be afraid before them; for it is the Lord your God that advances with you in the midst of you, neither will he by any means forsake thee, nor desert thee.
Deuteronomy 31:8 And the Lord that goes with thee shall not forsake thee nor abandon thee; fear not, neither be afraid.
Joshua 1:5 Not a man shall stand against you all the days of thy life; and as I was with Moses, so will I also be with thee, and I will not fail thee, or neglect thee.
Hebrews 13:6 So that we may boldly say, The Lord [is] my helper, and I will not fear what man shall do unto me.
Psalms 117:6 The Lord is my helper; and I will not fear what man shall do to me.
Above is the last one.