Q. I know the verse in the Torah about not boiling a kid in its mother’s milk (Ex. 23:19) is the basis of not mixing milk and meat. But why does the verse come not once but three times in the Torah?
A. The three verses are Ex. 23:19 which you quoted, and also Ex. 34:26 and Deut. 14:21. The three instances tell us three things:
1. Not to cook milk and meat together
2. Not to eat milk and meat together
3. Not to benefit from a mixture of milk and meat even if we do not ourselves eat it.
The kosher home requires the complete separation of milk and meat. It means a doubling up of crockery, cutlery, cooking utensils, washing-up facilities, etc., but in the end it becomes second nature and establishes a clear principle of kitchen organisation.