The One who appeared to Isaiah in his disappointment over the condition of the children of Israel was Christ as the Lord, the King, Jehovah of hosts (v. 5b; John 12:41 and note John 12:41). No matter what the situation might be on earth and regardless of the corruption and degradation among God’s people, Christ is still on the throne in His glory. The people had become fallen, but Christ and His throne remained the same in His glory. On this earth everything changes and fluctuates, but Christ remains the same today and forever (Heb. 13:8). Hence, we should not look down at the situation on earth but should look up to Christ on the throne (Heb. 12:2).

Christ’s long robe signifies Christ’s splendor in His virtues, which is expressed mainly in and through His humanity. That Christ was wearing a long robe indicates that He appeared to Isaiah in the image of a man. Christ is the God-man with the divine glory expressed in His human virtues.

Lit., stood. The seraphim signify or represent the holiness of Christ (v. 3). They were standing there for Christ’s holiness.

Or, it; referring to the train of His robe.

This was a praise rendered to Christ in His holiness. In this chapter Christ is seen in His divine glory (signified by the smoke — v. 4) with His human virtues (signified by the train of His robe — v. 1) held in His holiness (signified by the seraphim standing firmly — v. 2). Christ’s holiness is based on His righteousness (see note Isa. 5:16²). Because Christ was always righteous, He was sanctified, separated from the common people (Heb. 7:26). Cf. note Rev. 4:8^1b.

The meaning of the Hebrew is uncertain; the Septuagint translates this phrase as lintel.

The word in vv. 9-10 indicates that there would be no way for the people of Israel to be healed and recovered. Except for the word concerning the holy seed in v. 13, the prophetic warning in vv. 9-13, given in approximately 758 B.C., has been fulfilled. It was fulfilled beginning in about 605 B.C. by the Babylonian invasion and captivity (2 Kings 24, 2 Kings 25). This warning was quoted by the Lord Jesus in Matt. 13:14-15, and again by the apostle Paul in Acts 28:25-27, as a reminder to the rebellious and stubborn Jews under their ministry. Both the Lord’s reminding and the apostle’s reminding were fulfilled in A.D. 70 by the Roman army under Titus (Matt. 23:37-38; 24:2). Furthermore, after A.D. 70 this warning has been fulfilled throughout the centuries.

Isaiah was sent by the Christ who is full of the divine glory and the human virtues held in His holiness, to a people who were short of the divine glory, were violating the divine holiness, and were corrupt in the human virtues (v. 5). After sending the prophets to Israel, God sent His Son and then sent the New Testament apostles, to bring His chosen people into a state of living Christ (Phil. 1:21a) that they might express His divine glory with His human virtues in His holiness.

The words I and Us here indicate that the One speaking is triune, that this One is not merely Christ but Christ as the embodiment of the Triune God. See note Gen. 1:1³, par. 1.

Or, expiated. The more we see the Lord and are exposed, the more we are cleansed (1 John 1:7 and note 1 John 1:7^3b). According to our enlightened conscience, we are clean, but according to the actual facts of our situation in the old creation, we are not clean, for the old creation is unclean (see note Lev. 12:2¹ and notes on 1 John 1:8). After our body is redeemed (Rom. 8:23; Phil. 3:21), we will no longer be in the old creation. At that time we will be completely clean.

The ember from the altar signifies the effectiveness of Christ’s redemption accomplished on the cross.

Everyone who truly sees a vision of the Lord in His glory is enlightened in his conscience regarding his uncleanness (cf. Luke 5:8).

The shaking of the foundations signifies solemnity, whereas the temple being filled with smoke signifies glory burning in awe. The smoke signifies Christ’s glory (cf. Isa. 4:5).