Israel had a corporate identity that revealed a personal experience. Christ gives us a personal identity that is revealed in a corporate experience.
The individual found his or her identity by being part of the whole. The Law was given to the nation.
The Gospel is given to the individual and God builds His Church with individual building blocks.
"Now the LORD said to Abram, 'Go from your country and your kindred and your father's house to the land that I will show you. And I will make of you a great nation, and I will bless you and make your name great, so that you will be a blessing. I will bless those who bless you, and him who dishonors you I will curse, and in you all the families of the earth shall be blessed.' " - Genesis 12:1-3 ESV
Israel was the produce of one man. Blessing Israel blessed one man.
"As you come to him, a living stone rejected by men but in the sight of God chosen and precious, you yourselves like living stones are being built up as a spiritual house, to be a holy priesthood, to offer spiritual sacrifices acceptable to God through Jesus Christ. For it stands in Scripture: 'Behold, I am laying in Zion a stone, a cornerstone chosen and precious, and whoever believes in him will not be put to shame.' " - 1 Peter 2:4-6 ESV
Jesus is the cornerstone of a great house built from individuals.
Why is this different and important? God used the law to create the structure of His nation but God uses grace to create the structure of the Church.
"But as it is, God arranged the members in the body, each one of them, as he chose. If all were a single member, where would the body be? As it is, there are many parts, yet one body. The eye cannot say to the hand, 'I have no need of you,' nor again the head to the feet, 'I have no need of you.' On the contrary, the parts of the body that seem to be weaker are indispensable, and on those parts of the body that we think less honorable we bestow the greater honor, and our unpresentable parts are treated with greater modesty, which our more presentable parts do not require. But God has so composed the body, giving greater honor to the part that lacked it, that there may be no division in the body, but that the members may have the same care for one another. If one member suffers, all suffer together; if one member is honored, all rejoice together. Now you are the body of Christ and individually members of it." - 1 Corinthians 12:18-27 ESV
As individual believer priests we discover who we are as our gifts are manifested in the corporate experience. The ministry is not a nation and our loyalties are not national loyalties. The ministry is like a human body and our loyalties are organic in nature. Politics has it's place in a nation but not in a body. A nation must defend it's borders but if the individual has a strong identity in Christ the Church will have a strong presence because strong verticals make for stable horizontals.
"For no one ever hated his own flesh, but nourishes and cherishes it, just as Christ does the church, because we are members of his body." - Ephesians 5:29-30 ESV
This verse is given in the context of marriage and that married people are now 'one flesh' but it has broad application for us. Our lives are intertwined in ways we can not see or understand. Each person is important. Nothing is impersonal. We are one. Christ sees each individual as part of Himself. The Church as a whole makes up His physical existence in the world.