In 1974, Her Majesty's government fiddled about with the old county boundaries. Proud Lancastrians found themselves in Cumbria or Merseyside, and equally proud Yorkshire folk found themselves in the dreaded Lancashire. The photo below of the bridge over the Leeds Liverpool Canal was one of the old boundaries between the red rose and white rose counties, though it is now entirely Lancashire.
As you might expect, there is little difference in scenery either side of the bridge and some of the farms overlap both historic counties. In other words, it is possible to cross an important border without even realising it (I could have made this point more impressively with some European border, but my travel budget didn’t extend that far).
When you become a Christian, you may not feel any different. You're breathing the same air and wearing the same clothes as you were before you'd prayed the prayer. Yet an important border has just been crossed:
John 5:24: Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life.