The Christian is always the insider on the outside and the outsider on the inside.
The Christian is the insider on the outside because they are always engaged in the affairs of this world, since they are called by Christ to be in the world, and yet not of it. For a Christian to be involved in the intimate details of our common life, both private and public, yet without succumbing to the ever present idolatrous temptations from all sides, means they must have a concrete reference point from which to judge rightly the circumstances they find themselves in. And the concrete reference point is the very life and ministry of Christ Jesus.
It isn't some objective principle above and beyond the vagaries of history, as though that could give us any insight into what to do in the here and now. No. The Christian is guided in what they can and must do by the radical particularity of Christ's ministry to those directly in his midst. His kingdom spread as far, and only as far, as the sound of his voice and the touch of his hand. This is why he told his disciples the kingdom of God was in their midst.
The Christian is also never fully identified with the environment they find themselves in. The Christian is always a dual citizen, a citizen of whatever earthly city they are a part of, but also a citizen, indeed their primary citizenship, of a heavenly city called forth by God himself founded on Christ as the Cornerstone of a heavenly temple being built in the gritty details of our life here on earth.
The Christian is also always the outsider on the inside, because, while they are indeed residents of a heavenly city, they are also flesh and bone, blood and sweat, living breathing wounds and sins. The Christian recognizes within themselves every impulse, every desire, every hope and fear, of every person in their midst within earshot, eyesight, and physical touch. And again this understanding must be held, not by relying on some theoretical understanding of their corporate and individual creatureliness and fallenness, but with a tangible, indeed visceral SENSE of how this exists and is played out in their own day to day life.
And likewise the concrete reference point for the Christian to be able to get an accurate sense of this reality comes to them through the life and ministry of Jesus of Nazareth. The Christian sees and begins to understand the reality of their own beauty, sorrow, wounds, sins in their majestic broken tapestry only by looking upon the particular hands, feet, eyes, limbs, minds, pulses of those directly touched by Christ the Lord. Thus the Christian sees each wound, each cry, each laugh, each hidden sigh as uniquely belonging to the one owning these experiences as they do themselves, knowing that Christ's word and touch heals and reproves each according to their need.
As Christ has done for us, we are called to do for one another.