The 16th of December commemorates the Battle of Blood River - where less than 500 Boers stood their ground against 15k to 30k savages. The Boers emerged victorious from the seemingly impossible battle with only 3 injured and thousands of dead Zulus.
Prior to the battle, the besieged Boers made a vow which promised that if God would protect them and deliver the enemy into their hands, they would build a church and commemorate the day of their victory as if it were an annual Sabbath day to be honoured by them and their descendants.
Since then the Boers have celebrated the 16th of December as the Day of the Vow (Geloftedag). This battle and the preceding Vow manifests the birth of the Boer volk's origin myth: overcoming overwhelming odds in order to conquer some of the harshest terrain on earth thanks to the grace of God.
The only thing that ParSoc absolutely means is Mutual Aid, and Protection.. it can be in business, geography, religion, or hobby.
The goal is to find and coordinate with others to increase our chances of survival.
Those who don't understand this always focus on homesteading exclusively, but that is only one avenue that ParSoc may be worked out.