Isaiah 28 is possibly the clearest presentation of God’s people being made up of two groups: counterfeit believers and true believers.  The intention of chapter 28 is to move true believers towards trusting God’s invitation to rest in Him.  Verses 12 states why Ephraim and its leadership were to be judged: “to whom [the Lord] said, ‘This is rest…’; yet they would not hear.”  In contrast to Ephraim, true believers do listen to God’s Word, they trust in God’s “precious cornerstone” (v. 16), and they experience the results: “Whoever believes will not be in haste.”  Chapter 28 forces us to look at all the stressors in life that cause us to worry and be anxious.  It forces us to look at the times when we’re tempted to believe that God cannot deliver us. It forces us to look at all those other sources of rest we might be tempted to trust.  The example of Ephraim and the leadership teaches us to “go and do otherwise.”  By exposing their unbelief, Isaiah urges true believers to believe in Christ and to live out that faith in the form of righteousness.

Isaiah 26:1-8 reads like a Psalm.  It also functions like a Psalm since it is designed to urge us to sing its words.  The fact that it begins, “In that day this song will be sung…”, means it functions like all biblical prophecy–it shows us a picture of the future to urge true Believers to sing it now.  So, because of our relationship to God through faith in Christ and the power of the Spirit, we can now sing about our existence in this strong city (v. 1), we can evaluate whether we are citizens who are allowed to enter God’s city of salvation (vv. 2, 4-6, 8), and also enjoy city life characterized by “perfect peace” and a “level” path (cf. vv. 3, 7).  Our Savior makes it all possible for us as He experienced on the Cross the humiliation expressed in vv. 5-6 for us.  The songs of Isaiah, like so many Psalms, are designed to be experienced by Believers.  We sing these words to the extent that we experience the status they describe.  Prophecy moves us to adopt this lifestyle of trust and obedience (cf. v. 8).

Isaiah 25 sounds like a Psalm of praise.  God’s people are exalting God because of all the “wonderful things” He has done for them.  After two expressions of intentions (“I will…I will…” in v. 1), a series of explanations (“For you have…”) make up the largest part of the praise-prophecy.  When you arrive at v. 6, the prophecy shifts to what the Lord will do.  Verses 6-8 present a quality of life that everyone wants to experience.  Isaiah is urging the Church to be sure they will be there in that day.  Verse 9 presents the condition: “…this is our God; we have waited for him…”  Isaiah intends for their future confession to be our confession now.

Isaiah 19:18-25 presents a bizarre look at “that day” when even some people from God’s notorious enemy nations will be saved.  Israel’s problem in Isaiah has been the tendency to trust the nation, Assyria, for help (cf. also 2 Kings 16:7).  In vv. 18-22 Isaiah shows us what will happen to some individuals because of God’s activity.  Verse 21 shows what they will do and their actions become an example for every Believer to follow.  Also important for the Church is to be sure that we will be in this trio of blessed people: Egypt, Assyria, and Israel.  Of course, that requires that we are working now with God in making Himself known to the nations.  It’s His mission; it’s our mission.  Remember that prophetic Texts are designed to drive us toward more holiness and faithfulness.  This picture of God’s future day is a day we participate in partially now because of Christ’s accomplishments.  It’s not just will Christians be in on that day, but how are we participating in part of that day now through faith in Christ.  This angle fits many Old and New Testament prophetic and visionary Texts.