NEW DELHI — Even as gay activists in India celebrated on Friday, a day after a landmark Supreme Court ruling ended the country’s ban on gay sex, they were preparing for resistance to the decision.

Among the pressing questions left unresolved by the ruling: Will the authorities drop the countless criminal cases that had been filed under the Victorian-era law that had made consensual gay sex a crime? What will happen if a gay couple shows up at a registrar’s office and asks to be married? Will gay people be able to pursue cases of harassment based on sexual orientation?

At the forefront of many people’s minds was how to translate the court’s lofty language — “History owes an apology” to gay people, one justice said — into practical gains. India is still a deeply conservative, incredibly diverse nation of 1.3 billion that often feels more like a continent than a country.

Keshav Suri, 33, a Delhi-based hotelier and one of the more than two dozen petitioners in the case, was feeling rather optimistic on Friday. He said he hoped the ruling would be used to address hate speech against gay people. Personally, he said, he was planning to seek legal recognition of his recent marriage to a Frenchman.