The manslayer was safe not because he was innocent but because he was inside, and he went free at the death of the high priest. Hebrews says believers have fled for refuge.
The Shadow
God set aside six cities where a manslayer, someone who had killed unintentionally, could run from the avenger of blood; deliberate murder found no shelter there. The roads were maintained and the gates stayed open, and the moment you crossed the threshold, the avenger could not touch you. Notice what made the refugee safe. Not his innocence: someone was dead because of him. Not a verdict: no judge declared him not guilty. What made him safe was a city he did not build, with walls he did not raise. His survival was positional, not behavioral. And what set him free was the death of the high priest: a life not his own, ending in a death not his doing, releasing him from a debt he could never work off.
The Fulfillment
Hebrews uses the image directly: we “have fled for refuge to lay hold of the hope set before us.” Jesus is the city. The gate is never locked (“I am the door”), the access never depends on your qualifications, and the protection is positional: there is therefore now no condemnation to those who are in Christ Jesus. “In Christ” is not a metaphor. It is your location.
Then the type shatters in the best way. The old refugee went free when the high priest died. Your High Priest died carrying the debt of the whole human race, and then He walked out of the grave. The old priest's death ended the sentence; your Priest's endless life guarantees the freedom. There is no gap in the coverage, because the One who holds it does not expire.
Him All Along
If you still flinch when you fail, still pull back from God after a bad week as though the gate might swing shut, you are living like the avenger is still chasing you. He is not coming. You are not on probation. You are inside the city, and the anchor of your soul is fastened behind the veil, to a Priest who is alive, seated, and permanent.