Existence must exist at all times.

[ApeNotKillApe]

There's an idea goes that if you were to travel back in time all the way to the beginning, the mass in the universe would become increasingly dense as space contracted into itself. Consequently the passage of time would get slower and slower until it became infinitesimal. Theoretically you would eternally get closer and closer to the beginning of time without ever reaching it. This would mean is that in a sense the universe is both finite and eternal.

I have no idea if this actually holds water but it seemed to make sense, and it's an interesting thought anyway.