"Bekah is an incredible woman and I could see myself one day falling in love with her," Arie wrote in his People blog. "I was afraid and I was hesitant [to give her a rose] but went for it because I knew she was worth the risk."
Arie, 36, enjoyed a one-on-one date with Bekah in South Lake Tahoe during Monday night's episode of Season 22.
"Watching this back, I could see that Bekah M.'s age was becoming the topic of conversation in the house," Arie wrote.
"I have to admit, I knew she was probably one of the younger women, but you wouldn't think so by speaking with her."
Arie and Bekah's chemistry was off the charts leading up to their first one-on-one date, but both individuals needed to discover if they had a deeper connection beyond the physical.
"As I stood at the horse stables waiting to see Bekah for the last date of the week, I knew I needed this one-on-one to figure out if we had a future... or really if she felt ready for the future I was envisioning for myself," explained Arie, who has told multiple women his life is "boring" now and he enjoys going to bed early.
"As we road through the trails and arrived to our sexy hot tub in the woods, I just wanted to live in the moment with her."
The pro racing driver turned real estate agent added, "Bekah has way of making our time together feel easy and effortless, but in the back of my mind I knew that by the end of our date I'd need answers to some of my questions."
While the couple rode horses, kissed in a secluded hot tub and enjoyed dinner by a warm fire, the other bachelorettes gossiped and discussed how Arie would and probably should be bothered by his 14-year age gap with Bekah.
But up until this date, Bekah had found ways to conceal her age from Arie, and she had done nothing but impress the Bachelor and keep him on his toes.
"At this point in this journey, some of my most interesting, challenging and thoughtful conversations had been had with her," Arie wrote of the poised and mature nanny from Fresno, CA.
"Heading into that evening, I was ready to go deeper with Bekah and see if our lives match up for what we are looking for."
During the dinner portion of the date, Bekah casually dropped the bomb that she's 22, and Arie appeared surprised and disappointed. He said he wasn't looking for a girlfriend; he was looking for a wife.
"After finding out that Bekah was 22 years old, I have to say it was shocking. I appreciate what she said about not wanting me to see her through the lens of her age -- and up to this point I truly hadn't," Arie revealed.
"So far everything about Bekah that I had gotten to know led me to believe she was wise beyond her years. I felt like it would have been wrong and I'd regret it if I didn't give her the rose only based on age."