In 1Peter 1:3 Peter begins his letter with an accolade of the Father for the great salvation he has provided for us. The word blessed (G2128 – eulogetos) is an adjective which the writers of the New Testament use only to describe God. It is not so exclusively treated in the Septuagint, but even there the word is meant to show great respect for or to celebrate the one to whom it is addressed. The participle (G2127 –eulogeo) is used to refer to Christians, but the adjective (G2128) is used only to praise and celebrate God. It is also significant that Peter says “Blessed be the God and Father of our Lord, Jesus Christ…” in his doxology, in contrast with “Blessed be the God of Israel”, which was often used in the Old Testament or before Christ (cf. Luke 1:68). No doubt Peter meant to express the fact that Israel, as a nation, had rejected their Messiah, and only those who had received Jesus as their Savior and Lord were then and are now the recipients of God’s grace and peace in abundance (1Peter 1:2; cf. Isaiah 55:1-7).
Peter claimed that the God and Father of our Lord, Jesus Christ has begotten us again, i.e. made us alive again. The sense is that we were first begotten in Adam but are considered dead, for everyone dies in Adam’s race, without exception. However, the Father of our Lord, Jesus Christ, has begotten us again, not into a dying race like that of Adam, but into a new creation found in Christ (2Corinthians 5:17). He did this through Jesus’ resurrection. Because God made Jesus alive through the Resurrection, we, who are in him, have been reborn into a new creation (cf. Colossians 1:15-16). For, as the Scripture claims in Adam all die, but in the last Adam (Christ) all are made alive (1Corinthians 15:22).
Peter refers to this as a living hope. In other words, the hope of Peter’s readers was not yet fully possessed, but it was greatly anticipated (cf. Romans 8:24). This hope is the very foundation of our faith (trust) in God (cf. Hebrews 11:1).
The Father of our Lord and Savior, Jesus Christ, has begotten us into an immortal inheritance (1Peter 1:4). Peter uses a play on words to describe the fact that we shall never die. First of all, he claims our inheritance is immortal (G862 – aphtharton – it cannot be destroyed, i.e. by death). So, whether we live or whether we die, our inheritance in Christ cannot be destroyed. Additionally, our inheritance or salvation is stainless (G283 – amianton – it cannot be defiled from without by evil). That is, our sins are unable to mare the great salvation God has provided for us in Christ, Jesus. Finally, our inheritance in Christ doesn’t grow weak (G263 – amaranton – it cannot decay from within, i.e. by time / age). Paul claims 1Corinthians 15:52-54) that this will occur at the last trump, when the dead in Christ will be raised immortal (G862) – aphthartoi), and we, who are alive, will be changed (G236 – allasso).
Ultimately, our inheritance is our immortal body, and it is kept in heaven by God for us. Jesus described it in what the translators rendered mansions (John 14:2). The same Greek word (mone – G3438) is used in John 14:23 where the Father and Jesus make their abode in the believer. Moreover, Paul tells us in 2Corinthians 5:1 that, if we die (our earthly body being destroyed), we have an immortal dwelling made by God specifically for each one of us – preserved for us in the heavens, and we shall be clothed with it (1Corinthians 15:53). It is kept by God for us (1Peter 1:4), so that we could be witnesses of this great salvation found in Christ to those who abide in Adam, because the Scriptures imply that mankind, i.e. those in Adam, would ruin all God gives them in life, if immortality could be had as a natural inheritance from Adam (cf. Genesis 3:22-24). Salvation can be found only in Christ, Jesus!
 See Genesis 24:31; 26:29; Deuteronomy 7:14; Judges 17:2; Ruth 2:20; and 1Samuel 15:13.
 The NT writers treat the word (G2128) differently from the word used of man in the Beatitudes (G3107 – makarios). The word translated blessed there is a different Greek word. Makarios (G3107), which Matthew uses in Matthew 5, has to do with happiness. In his first epistle Peter uses eulgoetos (G2128), also translated blessed in the English, for one who is well spoken of or praiseworthy.