Why did Dev become suspicious when the Sanyasi returned to Dahanu a month later?

Dev's suspicion arose because the Sanyasi returned much sooner than expected. According to the account in Chapter 40, Dev had specifically told the Sanyasi to come back after two to four months, as the current time was not suitable for a collection. When the Sanyasi reappeared in a tonga after only about a month had passed, Dev became doubtful. He wondered if the Sanyasi had forgotten their previous conversation, and this premature return was the primary source of his suspicion, making him question the Sanyasi's motives for being there.