Romans 8:28 tells us God is working everything together for the good of those who love him and “are called according to His purpose” What does “his purpose” mean? Do all things work for the good only for those for whom God has a special purpose; a special task?
Ephesians 3:10-11 gives us the answer to your question. “His (God’s) intent was that now, through the Church, the manifold wisdom of God should be made known to the rulers and authorities in the heavenly realms, according to His eternal purpose which He accomplished in Christ Jesus our Lord.”
When sin came into the world, God had a huge problem. His righteousness demanded that every sin be punished, but His love wanted every sin to be pardoned. God can not express one of His attributes at the expense of another. Everything has to be reconciled. There had to be a way that would both meet the requirements of His righteousness and the desires of His love.
His intent was to demonstrate to the angelic realms that He could solve this seemingly unsolvable problem. The solution was for Him to send His own perfect son to pay the penalty for all the sins of mankind. Then everyone who accepted that payment in faith would receive a full pardon for their sins and inherit eternal life. Perfect righteousness would be achieved in the death of His son. No sin would remain unpaid. Perfect love would be achieved in the free gift of salvation to all who believe. Everyone who asked would receive. No one would be turned away.
He accomplished this through the Church, the body of believers. We have expressed our love for Him, and we have been called according to His purpose. Everyone of us can be certain that the promise of Romans 8:28 was intended for us.