Respect not thou their offering - There was no danger of this: they wished to set up a priesthood and a sacrificial system of their own; and God never has blessed, and never can bless, any scheme of salvation which is not of his own appointment. Man is ever supposing that he can mend his Maker's work, or that he can make one of his own that will do in its place.

separate

Genesis 19:15-22 And when the morning arose, then the angels hastened Lot, saying, Arise, take your wife, and your two daughters, which are here...

Jeremiah 5:16 Their quiver is as an open sepulcher, they are all mighty men.

Acts 2:40 And with many other words did he testify and exhort, saying, Save yourselves from this untoward generation.

2 Corinthians 6:17 Why come out from among them, and be you separate, said the Lord, and touch not the unclean thing; and I will receive you.

Ephesians 5:6,7 Let no man deceive you with vain words: for because of these things comes the wrath of God on the children of disobedience...

Revelation 18:4 And I heard another voice from heaven, saying, Come out of her, my people, that you be not partakers of her sins...

that I may

Numbers 16:45 Get you up from among this congregation, that I may consume them as in a moment. And they fell on their faces.

Numbers 14:12,15 I will smite them with the pestilence, and disinherit them, and will make of you a greater nation and mightier than they...

Exodus 32:10 Now therefore let me alone, that my wrath may wax hot against them, and that I may consume them: and I will make of you a great nation.

Exodus 33:5 For the LORD had said to Moses, Say to the children of Israel, You are a stiff necked people...

Psalm 73:19 How are they brought into desolation, as in a moment! they are utterly consumed with terrors.

Isaiah 37:36 Then the angel of the LORD went forth, and smote in the camp of the Assyrians a hundred and fourscore and five thousand...

Hebrews 12:28,29 Why we receiving a kingdom which cannot be moved, let us have grace, whereby we may serve God acceptably with reverence and godly fear...

Conflict.
"Therefore let us also, seeing we are compassed about with so great a cloud of witnesses, lay aside every weight, and the sin which doth so easily beset us, and let us run with patience the race that is set before us, looking unto Jesus the Author and Perfecter of our faith, who for the joy that was set before Him endured the Cross, despising shame, and hath sat down at the right hand of the throne of God. For consider Him that hath endured such gainsaying of sinners against themselves, that ye …
Thomas Charles Edwards—The Expositor's Bible: The Epistle to the Hebrews