On Saturday (Dec. 4), George Strait performed the second of back-to-back Strait to Vegas residency dates, but that wasn't the only item on his calendar. It was also the singer's 50th wedding anniversary with his wife, Norma.

The big milestone wasn't lost on Strait, and he carved out some time during his set to pay tribute to his wife, who was sitting in the live crowd. He dedicated a performance to Norma and briefly reflected on their years together to the audience before introducing the song.

"So I was 19 years old ... and I knew this girl, Norma. She was 17, really hot," Strait recounted, pausing in between sentences as the audience erupted into cheers. "We went to Mexico and eloped ... 50 years ago today."

He then launched into a performance of "I Cross My Heart," one of the most romantic love ballads from his extensive catalog of hits. The song originally came out in 1992 as part of Strait's Pure Country album, It also appears in the soundtrack of the movie Pure Country, which starred Strait and was his acting debut.

The song, which was written by Steve Dorff and Eric Kaz, was a No. 1 hit for Strait at country radio. It conveys a fitting sentiment for any couple in love, but as a 50th anniversary tribute, its lyrical message is particularly apt.

"I cross my heart and promise to / Give all I've got to give to make all your dreams come true / In all the world, you'll never find / A love as true as mine," Strait sings in the chorus.

Norma smiled from her spot in the crowd as Strait serenaded her. Check out fan-captured video of the moment below:

Strait and his wife met in high school in Pearsall, Texas. In an interview with country radio station the Bull 100.3, the singer says Norma is "the first girl I ever loved," explaining how they got together after a brief period of uncertainty.

"We knew each other forever, growing up in a small town. I never really even thought anything about her, but then one day I asked her out and we went on a date. We didn't see each other for a long time after that," Strait says. "Then one day, I thought, 'I'm missing the boat here,' and we started dating again."

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