'Unless' in the Bible

And he said, “Well, how could I [understand] unless someone guides me [correctly]?” And he invited Philip to come up and sit with him.

Some men came down from Judea and began teaching the brothers, “Unless you are circumcised in accordance with the custom of Moses, you cannot be saved.”

other than for this one statement which I had shouted out as I stood among them, ‘For the resurrection of the dead I am on trial before you today.’”

Paul said to the centurion and the soldiers, “Unless these men remain on the ship, you cannot be saved.”