Stop. The Torah stops telling all the sequence of events this week, just to describe with detail a tiny event: how one person welcomes guests to his tent, how Avraham Avinu runs after three strangers to check how they are doing and to let them eat and drink.
Why? Because this is the most important thing. Because this is not a science or history book. The word "Torah" comes from the same root as the word Hora'ah (הוראה, instruction) - its purpose is to teach, to guide, to educate. Therefore it does not report almost anything about all the nations and kingdoms who rose and fell during that time period, but does stop and slow its pace when it talks about welcoming guests. Thousands of years are described in a few verses, but when there is an important human lesson - we should stop and learn and reach conclusions. All these "small" deeds, which no researcher would have dwelt on, are eventually the most meaningful and influential thing. It's a fact. Thousands of years after this guest-welcoming, we learn about it again this week.