It was a fitting Christmas present from one world renowned pot enthusiast to another.

The country music legend Willie Nelson lit up social media this week when he tweeted a photo of himself in a red and green sweater depicting a marijuana leaf adorned with lights and a star and “smoke weed everyday” printed in white letters.

The phrase is the famous closing line from the hip hop anthem “The Next Episode,” featuring Snoop Dogg. And, indeed, the sweater was a gift from the rapper himself.

“Thank you @SnoopDogg for the Christmas Sweater,” Nelson wrote.

While the exchange may have been, by some appearances, a lighthearted attempt to plug Snoop Dogg’s clothing line (when he reposted the picture of Nelson on Instagram, he linked to his online store), it was nothing out of the ordinary for the two artists. For years now, the 83-year-old king of outlaw country and the 45-year-old hip hop star have maintained a warm, humorous and utterly adorable friendship, formed over – but not necessarily defined by – their mutual love of marijuana, which both have long celebrated in their songs and public appearances.

As the story goes, Snoop Dogg and Nelson’s bond blossomed in a haze of pot smoke one day in the Netherlands in 2008. Esquire journalist Andy Langer had gotten high with them back-to-back the previous year and wrote about it for the magazine.

“I vaguely recall asking Willie if he’d ever sparked up with Snoop Dogg. Nope,” Langer wrote. “From stoner small talk, a seed was planted. I could be their link – a bridge between the marijuana culture’s two most identifiable connoisseurs.”

It took some 15 months, but in April 2008 – on 4/20, to be exact – Nelson was in Amsterdam to play a concert, when Snoop Dogg called him and asked if he wanted to collaborate on a song. Rather than wait until he returned from the tour, Snoop Dogg took a flight to join him. The two performed together and later sat down to write. Snoop Dogg described what happened next in an innuendo-laden appearance on “The Tonight Show”:

“I was in his hotel room, and we was playing dominoes and enjoying life. After enjoying life … we developed a hunger. … Naturally, we wanted to go to Kentucky Fried Chicken, which is one of our favorite spots, his and mine. So we pull up in the drive-through, we order the chicken, they give it to us, and they hand us the big bucket. We take the top off and we both put our hand in at the same time. And we grab the same piece of chicken at the same damn time. And I said, You know what Willie? That’s yours. Go ahead, take that, dog.”

The song that emerged from the meeting was “My Medicine,” an upbeat half-country-half-rap ode to marijuana that landed on Snoop Dogg’s 2008 album “Ego Trippin’.” The video features shots of Snoop Dogg and Nelson huddled around a studio microphone, grinning and singing the chorus together.

It was the beginning of a beautiful bromance – one that Snoop Dogg forcefully defended two years later. In 2010, when Nelson was arrested and charged with misdemeanor marijuana possession, Snoop Dogg ripped into the officers who busted him at the Sierra Blanca highway checkpoint near El Paso.

“What you think you’re gonna gain by arresting Willie Nelson? He got out and he back smoking right now,” he told TMZ at the time, shouting profanities about police. “If you’ve got a problem with Willie Nelson, you’ve got a problem with me.”

For what it’s worth, Snoop Dogg was later arrested on marijuana charges at the same checkpoint. If Nelson had similar words for authorities, they haven’t been made public yet.

In 2011, the pair collaborated again, this time on a Snoop Dogg track called “Superman.” Released that same year, the song represents perhaps the peak of their musical partnership. The song is jocular overall, but it riffs on the serious themes of mortality and burning out: “I’m tryin’ to do more than I can,” the two sing over a simple acoustic guitar line, “I got a little outta hand, I wasn’t Superman.”

The video features shots of them smoking, eating lunch and riding in a car, along with clips from a concert they played together. “So we got Snoop to come all the way over here to sing and record with us,” Nelson tells a crowd of people from the stage. Snoop Dogg emerges, saying “I love this man right here!”

The third track they worked on together was a 2012 Nelson song called “Roll Me Up and Smoke Me When I Die,” which featured a verse from Snoop Dogg, as well as vocals by country musicians Kris Kristofferson and Jamey Johnson. Like “Superman,” it takes a tongue-in-cheek look at death, and like “My Medicine,” it too is something of an ode to the pair’s substance of choice:

Roll me up and smoke me when I die

And if anyone don’t like it, just look ’em in the eye

I didn’t come here, and I ain’t leaving

So don’t sit around and cry

Just roll me up and smoke me when I die

When it comes to their actual marijuana consumption, Snoop Dogg has conceded that Nelson, nearly twice his senior, can smoke him under the table. “Only person that [ever] smoked me out is Willie —– Nelson!!!” he once tweeted. By Nelson’s account, he and Snoop Dogg had a “smoke-off” in Amsterdam “and he crawled away,” he told GQ last year.

In the end, however, it’s Nelson’s life of musical accomplishment that Snoop Dogg seems to admire most.

“Willie Nelson is a legend,” Snoop Dogg told TMZ after Nelson was arrested. “Y’all sometimes need to back up off certain people and have a certain amount of respect for your elders. Willie Nelson is our elder. He is somebody who lived through many decades of music and hard times and whatnot, and living good and going up and down. So give him that respect.”