Parent: Account

Child: Payment__c

trigger myPaymentTrigger on Payment__c (before delete, before insert, after update) {

List<Payment__c> obj =new List<Payment__c>();

//Account a = new Account();

 if(trigger.isInsert || trigger.isUpdate){

   obj = trigger.new;

   Account a = ; //Here i want to write Query that should return Parent Account of Payment__c

}

  if (trigger.isDelete) { }

}