EXCLUSIVE: John Legend Reveals the Moment He Fell in Love With Chrissy Teigen

It was love at first text for John Legend and Chrissy Teigen!

The 37-year-old singer sat down with ET on Friday to promote his new movie, Southside With You, based on Barack and Michelle Obama's first date. But it was his own love story he couldn't stop talking about!

WATCH: John Legend on Life With Chrissy Teigen and Baby Luna: It's 'Powerful to See a Product of Your Love'

"I fell in love with her over the phone because she is good with those 140 characters," Legend joked, when asked when he fell in love with the Sports Illustrated model.

"[At the beginning of our relationship] we were texting a lot, and I started to see her sense of humor," he elaborated. "We would talk on the phone, and I started to fall in love with how engaging and witty and funny she is."

"And I think that's when I really started to know that this was the kind of person I wanted to around a lot," the "All of Me" singer shared. "Once we started spending more time together between tour stops and all this other stuff, we realized we had such a connection -- and then it blossomed into a marriage and a baby."

"I wasn't nervous about it," Legend continued. "When you feel a real connection to somebody, for me it wasn't nerves, it was more like excitement. 'Oh, this could be great.'"

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Perhaps it's Legend’s own love story that inspired him to tell Barack and Michelle Obama's romantic tale. The GRAMMY winner serves as executive producer on Southside With You, and even wrote a song for the film.

"The movie is such a great love story and makes you feel their romance, and it makes you believe in the power of love and of people finding the person that is really the right match for them," Legend said. "The song [I wrote] is called 'Start,' and the idea behind the song is we don't know unless we start, so we have to try it. We have to engage."

"I felt like that was the message Barack was trying to give to Michelle in the film," he added.

And as for how the Obamas have reacted his vision of their love story? Well, Legend is still waiting for their feedback. "I told them about it the last time I saw them and encouraged them to see it, and we will make sure they get a copy if they haven’t seen it yet," he said. "I think they will like it."

Southside With You hits theaters on Aug. 26.

WATCH: Barack and Michelle Obama Go on Their Romantic First Date in 'Southside With You'

ET recently sat down with the film's first lady, Tika Sumpter, who also couldn't wait to hear the Obamas' reaction.

"I put so much work into it," she said, tearing up. "I just hope she likes it."

See more in the video below.

'Southside With You' Shows Never-Before-Seen Side of Barack and Michelle Obama

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