Indian Contract Act, 1872 · Chapter IV: Of the Performance of Contracts · Performance of reciprocal promises
Section 57: Reciprocal promise to do things legal, and also other things illegal
In plain words
Where parties promise to do certain legal things and, in specified circumstances, certain illegal things, the first set of promises is a contract and the second is a void agreement.
Example: A agrees to sell B a house for 10,000 rupees, but to charge 50,000 rupees if B uses it for gambling. The sale for 10,000 rupees is a contract, and the gambling term is void.
A simplified explanation, prepared with AI assistance from the official text below and checked automatically against it for numbers and cross-references. The official text is the law and prevails over this summary. Not legal advice.
Official text
Where persons reciprocally promise, firstly, to do certain things which are legal, and, secondly, under specified circumstances, to do certain other things which are illegal, the first set of promises is a contract, but the second is a void agreement.
Illustration
A and B agree that A shall sell B a house for 10,000 rupees, but that, if B uses it as a gambling house, he shall pay A 50,000 rupees for it.
The first set of reciprocal promises, namely, to sell the house and to pay 10,000 rupees for it, is a contract.
The second set is for an unlawful object, namely, that B may use the house as a gambling house, and is a void agreement.
Source: India Code (indiacode.gov.in), the consolidated text published by the Legislative Department, Government of India. Text as updated on India Code on 15 October 2026. Words in square brackets [ ] were inserted or substituted by later amending Acts, and *** marks words omitted by an amendment. The amendment footnotes are not reproduced here. Official text on India Code.