en_tn/act/12/10.md

After they had passed by the first guard and the second

It is implied that the soldiers were not able to see Peter and the angel as they walked by. AT: "The first and second guards did not see them as they passed by, and then" (See: rc://en/ta/man/translate/figs-explicit)

had passed by

"had walked by"

and the second

The word "guard" is understood from the previous phrase. AT: "and the second guard" (See: rc://en/ta/man/translate/figs-ellipsis)

they came to the iron gate

"Peter and the angel arrived at the iron gate"

that led into the city

"that opened to the city" or "that went from the prison to the city"

it opened for them by itself

Here "by itself" means neither Peter nor the angel opened it. AT: "the gate swung open for them" or "the gate opened itself for them" (See: rc://en/ta/man/translate/figs-rpronouns)

went down a street

"walked along a street"

left him right away

"left Peter suddenly" or "suddenly disappeared"