What is the ruling on buying a house by paying 500,000 LBP to the bank, after which the bank pays 1,000,000 LBP after 6 months, and the remaining 500,000 LBP is paid back to the bank in easy installments?

This transaction falls under the category of "lend me, and I will lend you," which is forbidden by the Hanbalis and Hanafis, and disliked by the Malikis, though the predominant view among them is also that it is forbidden. The prevalent opinion is that it is impermissible because every loan that brings a benefit to the lender is usury (riba), and because this loan helps the bank in its usurious investments, which constitutes cooperation in sin and aggression.

Therefore, one must avoid such dubious transactions.