Why do parents put their elbow in water before taking their baby for a bath
To test the temperature of the water, that part of the arm is more sensitive than the hands to heat. They don't want to burn the baby with water that is too hot.
A parent puts his or her elbow in water before taking their baby for a bath so as to test if the water is of the right temperature or warm enough. Another reason is that the elbow is the only part of the arm that is sensitive and can tell if the water is too hot for the baby. Read more details at http://www.babble.com/baby/baby-care/complete-guide-to-bathing-your-baby-bath-baby-baby-bathtub/bath-how-to-bathe-tub-3/.
To make sure the water is not to hot like warming a bottle an dropping a few drops on the inside of your wrist
I never used my elbow but its to check the water temp. You want to make sure it's comfortable for the little angels
Test the temperature