The funds of a building and loan association, existing under this Code or any other law of this State, shall not be invested in any corporation stocks. Nothing herein contained shall prevent a building and loan association from purchasing and acquiring stock in the Federal Home Loan Bank under the provisions of the Act of Congress known as the Federal Home Loan Bank Act [12 U.S.C. § 1421 et seq.], or prevent a building and loan association from acquiring any corporation stock to secure itself against loss of money owing to it by any borrower. The stock so acquired under the last preceding clause shall be sold within 60 days after the State Bank Commissioner shall direct.