Pressure is the stuff The Bachelor drama is made of. On the Monday, March 11 season finale of the hit ABC dating show, Sean Lowe will be dropping to one knee to propose marriage to one of his two finalists -- Catherine Giudici and Lindsay Yenter -- and the decision wasn't an easy one.

Sources close to the show tell Us Weekly that the 29-year-old entrepreneur was very serious about his feelings, and was a ball of nerves by the time the morning of the proposal rolled around.

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"Even on the morning of the proposal, he was still thinking about what to do," a show source tells Us of Lowe's anxiety prior to the finale in Thailand.

The usually cool-headed bachelor even pulled both Giudici, 26, and Yenter, 24, aside off-camera during their last days in Thailand to grill them with some very hard-hitting questions.

"These weren't loving chats," the source said. "These were nervous, freaked-out chats. … They discussed faith, family and what their futures would look like."

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Lowe, who is a born-again virgin and is abstaining from sex until marriage, also memorably spent his time alone with each of the finalists in the Fantasy Suites engaged in hours-long discussions.

"Sean's not someone who just got caught up in the moment," another insider tells Us. "He was serious about finding a wife, and he didn't want to make the wrong decision."

In December, Lowe opened up to Us about his journey to find love, and admitted that he hadn't expected to feel so strongly for two different women.

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"I had no idea I would become so attached and emotionally invested in multiple women," he told Us at the time. "I've always thought that would be so hard to do. But it can happen, and it did happen."

Find out who Lowe picks on the season finale of The Bachelor, airing on Monday, March 11 on ABC.

This article originally appeared on The Bachelor: Sean Lowe Had "Nervous, Freaked-Out Chats" With Finalists Catherine Giudici and Lindsay Yenter