1 Peter has an overriding theme of suffering. In both 1 Peter 1:6 and 1 Peter 4:12, Peter refers to suffering in terms of a fire. I imagine that this is a common metaphor in cultures throughout time, all the way was back to OT times.
Just as fire burns away perishable stuff, so testing in our lives strips away everything about our faith that is not God.
When circumstances take our money and we get upset, we find that our satisfaction was not God alone. It was God plus money.
When our physical health declines and we get upset, we learn that God was not enough for us. We believed in God plus physical health.
When our marriages suffer, or our family goes astray, we find that God was not enough. It was God plus …
And when, in the midst of suffering, we turn away from God, we are demonstrating that the gospel we believe is really a prosperity gospel—a gospel that says, “I will trust God because he gives me comfort/money/health/good marriage/insert your own.” We think Jesus died to make us comfortable/rich/healthy/satisfied in marriage.
Thus, suffering is often God’s way of showing us what we really believe. It shows us how much more than God we think we must have.
In the fire of suffering, God is burning up everything that is not God in order to create a more genuine faith that is satisfied in God alone.
The truth is that we can live with a lot less than we have. But we cannot live without God.
So when God takes it, it’s okay, because it wasn’t yours anyway (he gave it to you), and you don’t need it (he is enough for you).