Monday. If you spend money on a Monday you will spend it for the week.
If you set oats on a Monday it will be a bad crop.
If visitors come on a Monday you will have visitors for the week.
If you go visiting on a Monday you will have bad luck for the week.
If you build a fence on a Monday it will fall down again.
If you go in service on a Monday you will not stay long in your job.
For health.Anaithnid