It is interesting that Peter reminds his readers that they have tasted the Lord, Jesus (1Peter 2:3), and what he might be calling to mind is one of Jesus’ parables that concerns the new and old wine (cf. Luke 5:39). Wine changes one’s behavior and being filled with the Spirit is compared with being drunk with wine in Ephesians 5:18. There Paul says we should not be drunk with wine, implying drunkenness changes one’s walk or behavior (Job 12:25; Psalm 107:27; Isaiah 29:9). Rather, we need to be filled with the Spirit and thereby our walk (behavior) would be changed for the better (Romans 8:1, 4; Galatians 5:16, 25).
The context of the Lord mentioning the new wine versus the old in Luke 5:39 has to do with believing the old (the Law of Moses) is good enough. Therefore the new (Jesus) isn’t needed. The KJV translates the Greek word, chrestos (G5543), as better, as though the Jews tasted both Moses and Jesus and prefer the old wine to the new, but this is not what the Lord claims in this parable. Rather, he says “No one, having drunk the old, desires the new!” In other words, the new (Jesus) is rejected out of hand, without trial.
What Peter means to say in 1Peter 2:3 is: “If, indeed, you have tasted that the Lord is Good,” that is, since you have tried him out and found that he is true to his word… He is quoting Psalm 34:8 “O taste and see that the LORD is good: blessed is the man that trusts in him.” One cannot know that the Lord is good, until one has trusted Jesus with his life. “If, indeed, you have tasted – hoped in, trusted – the Lord, and know he is Good…” This is what Peter means, in contrast to Jews who have rejected him out of hand.
In the context of the new wine (metaphor of Jesus) Peter refers to two different works. On the one hand was the work of men and the other of God. The leaders of the Jews had rejected Jesus out of hand for their work, Judaism, which needs no Savior (1Peter 2:4, 6). Jesus applied this same argument to himself (Matthew 21:42; Mark 12:10-11) and was actually quoting from Psalm 118:22-23. Nevertheless, Jesus was the Chosen One of God to be the Rock or Stone upon which a new work would be built, i.e. the Church (Matthew 16:18).
In his first argument Peter mentioned a living hope (1Peter 1:3) or eternal life, saying his readers are born again through the resurrection of Jesus. Therefore, rest in this living hope that God continually saves us throughout our lives from any trouble. In his second argument, Peter mentioned that his readers are born again of incorruptible Seed, which is the living Word (Logos) of God (1Peter 1:23), and this in contrast to the corrupt or cursed seed, which referred to the Levitical priesthood (cf. Malachi 2:1-3). We are called to be a kingdom of priests to God, a faithful house, as contrasted with the unfaithful house that went before us. Therefore, as God’s begotten sons (and new priesthood), don’t behave as the corrupt seed (old priesthood) has done (cf. 1Peter 2:1); rather desire the sincere milk of the word, behaving as harmless babes in the face of one’s enemies.
In his third argument Peter mentioned that his readers come (continually) to THE Living Stone, the Elect or Chosen One of God, resting upon him as their foundation. That is, they continually allow their behavior (viz. during the trial that has come upon them) to be gracious in the sight of the gentiles. In so doing, when the trial reaches its end, that is, when Jesus judges Jerusalem and the Temple, those who condemn Peter’s readers at the time of his letter would then glorify God, whose judgment had finally come upon the believers’ enemies.