var thedate   = new Date();
var dayofweek = thedate.getDay();
var hourofday = thedate.getHours();

function isShabbat() {
	// return TRUE if it's Fri after 6p, or Sat before 10p
	if ((dayofweek == 5 && hourofday > 18) || (dayofweek == 6 && hourofday < 22)) {
		return true;
	}
	return false;
}

if (isShabbat()) {
	document.location = 'isShabbos.html';
}