validity

1) What is essentially required for a valid baptism? 2) Would any private baptisms be valid? If not, what essential requirement does it lack? If so, why? 3) Would two random christians baptizing each other in the pool be valid (assume they’re genuine in intent and not joking)? If not, what...

From what i have seen and learned there can be times in the credo community where a person would either be rebaptized (perhaps not recognizing the RC baptism) or perhaps baptized multiple times throughout a life (perhaps after the repentance of what would be deemed a major sin). Would...