Confusing Contracts: Section 4 of Indian Contract Act vs. The World

Yaar, I'm really stuck here, hope someone can help. I've been trying to understand this Section 4 of the Indian Contract Act 1872, and honestly, my head is spinning. It says that "all agreements are contracts if they are made by the free consent of parties to the agreement capable of being enforced by law". But then, I started reading about the doctrine of consideration, and apparently, every contract needs consideration (Section 26). But wait, the Supreme Court in the case of B.N. Lokur v. State of U.P. (2000) cited Section 4 as the basis for voiding a contract where consideration was absent. So, my question is: if Section 4 is saying all contracts are valid if they have free consent, then why is consideration required in the first place? I'm really confused here.