Hebrews 2:4

Heb. 2:4. God also bearing (them) witness, both with signs and wonders, and with diverse miracles, and gifts of the Holy Ghost, according to his own will.

The exposition of this text shows as nothing else in this Hebrews commentary (with the possible exception of Hebrews 11:1), Edwards as apologist. Here he notes that

the word "witness," or "testimony" is often used in the New Testament; where such terms often signify, not only a mere declaring and asserting a thing to be true, but holding forth evidence from whence a thing may be argued and proved to be true. Thus (Hebrews 2:4), God is said to bear witness, with signs and wonders, and diverse miracles, and gifts of the Holy Ghost. Now these miracles, here spoken of, are called God's witness, not because they are of the nature of assertions, but evidences and proofs. So: "Long time therefore, abode they speaking boldly in the Lord; which gave testimony unto the word of his grace; and granted signs and wonders to be done by their hands" (Acts 14:3). And: "But I have greater witness than that of John; for the works which the Father hath given me to finish, the same works that I do, bear witness of me, that the Father hath sent me" (John 5:36). Again, "The works that I do in my Father's name, they bear witness of me" (John 10:25). So the water and the blood are said to bear witness (1 John 5:8), not that they spake or asserted anything, but they were proofs and evidences. So God's works of providence, in the rain and fruitful seasons, are spoken of as witnesses of God's being and goodness, i.e. they were evidences of these things. And when the Scripture speaks of the seal of the Spirit, it is an expression which properly denotes, not an immediate voice or suggestion, but some work or effect of the Spirit, that is left as a divine mark upon the soul, to be an evidence, by which God's children might be known. The seals of princes were the distinguishing marks of princes: and thus God's seal is spoken of as God's mark, "Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads" (Revelation 7:3); together with: "Set a mark upon the foreheads of the men that sign and that cry for all the abominations that are done in the midst thereof" (Ezekiel 9:4). When God sets his seal on a man's heart by his Spirit, there is some holy stamp, some image impressed and left upon the heart by the Spirit, as by the seal upon the wax. And this holy stamp, or impressed image, exhibiting clear evidence to the conscience, that the subject of it is the child of God, is the very thing which in Scripture is called the seal of the Spirit, and the witness, or evidence of the Spirit. And this image enstamped by the Spirit on God's children's hearts, is his own image: that is the evidence by which they are known to be God's children, that they have the image of their Father stamped upon their hearts by the Spirit of adoption. Seals anciently had engraven on them two things, viz. the image and the name of the person whose seal it was. Therefore when Christ says to his spouse, "Set me as a seal upon thine heart, as a seal upon thine arm" (Song of Solomon 8:6); it is as much as to say, let my name and image remain impressed there. The seals of princes were wont to bear their image; so that what they set their seal and royal mark upon, had their image left on it. It was the manner of princes of old to have their image engraven on their jewels and precious stones; and the image of Augustus engraven on a precious stone, was used as the seal of the Roman emperors, in Christ's and the apostle's times. And the saints are the jewels of Jesus Christ, the great potentate, who has the possession of the empire of the universe: and these jewels have his image enstamped upon them, by his royal signet, which is the Holy Spirit. And this is undoubtedly what the Scripture means by the seal of the Spirit; especially when it is stamped in so fair and clear a manner, as to be plain to the eye of conscience; which is what the Scripture calls our spirit. This is, truly an effect that is spiritual, supernatural, and divine. This is, in itself, of a holy nature, being a communication of the divine nature and beauty. That kind of influence of the Spirit which gives and leaves this stamp upon the heart is such that no natural man can be the subject of any thing of the like nature with it. This is the highest sort of witness of the Spirit, which it is possible the soul should be the subject of: if there were any such thing as a witness of the Spirit by immediate suggestion or revelation, this would be vastly more noble and excellent, and as much above it as the heaven is above the earth. This the devil cannot imitate: as to an inward suggestion of the Spirit of God, by a kind of secret voice speaking, and immediately asserting and revealing a fact, he can do that which is a thousand times so like to this, as he can to that holy and divine effect, or work of the Spirit of God, which has been now spoken of.