Laravel - Validation - Customizing The Error Messages
You may customize the error messages used by the form request by overriding the messages
method. This method should return an array of attribute / rule pairs and their corresponding error messages:
/**
* Get the error messages for the defined validation rules.
*
* @return array
*/
public function messages()
{
return [
'title.required' => 'A title is required',
'body.required' => 'A message is required',
];
}