Credit purchases of goods is credited to personal account.
Purchases A/c Dr. (Debit)
To Creditor/Trade Payable A/c Cr. (Credit)
Sundry Debtors comes under Personal Account & Golden rule for Personal Account.
This principle is used in the case of personal accounts. When a person gives something to the organization, it becomes an inflow and therefore the person must be credit in the books of accounts. The converse of this is also true, which is why the receiver needs to be debited.
Since to whom the goods are sold is at the receiving end and is Debited.