IF IN THE BOOKS OF ACCOUNTS ANY CASH CREDIT ENTRY IS PASSED...AND ASSESSE HAS NO ANSWER AND PROOF OF SUCH AMOUNT ...THAN IN THAT CASE....IN WHICH SECTION A.O. WILL CONCLUDE THE CASE...SECTION 68 OR 269SS..
Section 269SS- This Section is Like A GUIDELINE which tells that No person would take the Loan, Deposit or Specified sum exceeding Rs. 20,000 in cash. But this section does not tell anything about penal provision etc. But Section 271D is attached with this Section that means if any default is being made under 269SS then Penalty would be levied u/s 271D.
Section 68- This section is like a SHOW CAUSE NOTICE which seeks explaination. This Section Tells that if any cash amount is found credited in the books but it CANNOT BE EXPLAINED then it will be deemed as Income of that year in which it is found to be credited. Section 115BBE & Sec. 271AAC is attached with this which tells the treatment of amount find u/s 68.
DIFFERENCE-
Section 68 seeks for Explaination which means it can be used only when the amount found in the books is from UNKNOWN SOURCES.
On the Other hand, Section 269SS can be applied only when amount is KNOWN SOURCES and Received only as a LOAN, DEPOSIT OR SPECIFIED SUM (not any other purpose). While the type/purpose of amount find u/s 68 does not matter.
If any amount is found which is Loan+ From Unknown sources then that would be covered by Section 68 because as I said when anything is received from UNKNOWN SOURCES then purpose does not matter at all.