For many of the 7,000 home equity loan customers at Wells Fargo Bank in California, the message on their February statement may have told them the truth, but it was more than they truly wanted to know.

At the bottom of the letter, where there is usually a short marketing message, it read: "You owe your soul to the company store. Why not owe your home to Wells Fargo? An equity advantage loan can help you spend what would have been your children's inheritance."

Within 24 hours after customers received the statement, the Wells Fargo switchboard went crazy.

"Most customers reacted well," said Kim Kellogg, a bank spokesman. "But some were perplexed that this message would be sent out by Wells Fargo and most viewed it as some sort of prank."

After the barrage of phone calls, the head of the home equity loan division, James G. Jones, immediately sent out a letter apologizing to the 7,000 customers who received the statement. The bank also has set up an internal committee to investigate why it happened, who was responsible and how it could have been prevented.

Kellogg said the San Francisco-based company did not intend to put any message on the February statement, but somehow the computer that prints the statements picked up what was usually a test message. No one at the bank or the company that stuffs the envelopes and mails them caught the mistake before the letters were sent. Kellogg said the message on the statement is approved by bank officials each month, but that didn't happen this month.

Normally, the message tells customers about the latest interest rate or a new bank product. Last month, the bank printed the amount of interest the borrower had paid in 1987. It is possible that technicians changed the computer program to allow the test message to be printed on the statement.

"From now on, we're just going to type, 'Testing One, Two, Three' at the bottom," Kellogg said. "We're hoping it's over and done with now."