Massage oil is preferably applied warm to the body.
A simple and also budget-friendly way is this porcelain au bain-marie heater with tea lights. The water in it is heated to a comfortable temperature, it does not get very hot. In this water you place the oil bottle for about five minutes before the massage.
It is a safe way of heating without cables, plugs or sockets.
The heater is washable in the dishwasher.
The heater comes with 100 tea lights.