WHEELER & CHALK marriage licence bond

[fizzix]

I’ve just managed to take a step back with one of my ‘lot’ by finding the transcription of her marriage licence bond. Courtesy of Wiltshire FHS via FindMyPast.

Sarah WHEELER aged 22 m Richard CHALK aged 28 31/12/1733 in Downton, Witshire.

I have a couple of queries about other bits of info provided on the transcription:
1.   As she was over 21 why was a licence required?
2.   The bond date is given as 26/12/1733, I assume that this is the date it was issued?
3.   Bondsman is given as Samuel ARNOLD, tailor, Downton. Why? What would his relationship be?

Thanks for any input 

[stanmapstone]

Licences have nothing to do with age. Licences were popular with certain families, especially those that did not wish to have their domestic affairs paraded  before the other parishioners on the three Sundays that the banns were read. A Licence was popular because it had the advantage of relative speed as once the licence was issued then the marriage could take place.  A Licence was also popular because it facilitated a marriage in Lent when banns should not have been called. The licences were valid for three months,
By entering into a bond a person would agree for instance that a statement was true, for a marriage  that there was no "lawful let or impediment" to the proposed marriage. If this was not the case  a penalty was due to the church official concerned, a bondsman could be anyone, and not necessarily a relative.

Stan