new beginnings

Isn't the Sabbath, or Sunday technically the 7th day - our day of rest? Then why, psychologically, does it seem more like a new beginning to me? I kind of feel like IT is the day to start over- the day to give a new start to my new week? It is the day I usually make new plans for the upcoming week, the day I set new goals, the day I actually TRY to get motivated to do better in anything and everything - from being nicer to working harder at things like cleaning my van or eating healthy. Is Sunday the beginning or end of the week- to all of you?