What is "handfasting"
The true origin of handfasting is not known, but the typical modern handfasting ceremony is derived from the Celtic tradition, predating Christianity. It is a historical term for the word wedding and as couples in Celtic England could not wander down the high street to buy a gold ring, they used handfasting as their marriage ceremony. Gold bands were also the preserve of the aristocracy, so the relatively simple, but highly symbolic ritual of handfasting, was much more affordable.
Couples would pledge their intent and love by binding their wrists with strips of fabric torn from old garments, or cord from rope to symbolize their union and would then be tied till midnight. They would often then be escorted to the bed chamber to consummate their union. This part of the ceremony is clearly not necessary in the 21st century, and I have never been asked to stay and carry out this duty!
It was considered that if the couple survived the obstacles of life for the rest of the day then surely they would survive in marriage together. In the Scottish Celtic tradition, the binding would be for a year and a day and if after that they still wanted to stay together the handfasting was formally recognized as their wedding ceremony.