The Talmud Shabbat page 35 describes how there would be 6 blasts of a horn on Friday afternoon before Shabbat. One of the blasts was to call the workers in from the fields. The Talmud states that the workers were to come in all together. Rashi says they came in together so no one would be suspicious that someone would desecrate the Shabbat.
The Shikker Dovid finds a deeper meaning. They all came in together as the day waned and the sun began to set. One can imagine that being outside alone in those early days was not so safe from robbers, bandits or animals. They came in together out of concern for each other. We should learn the lesson of concern for others.