We caught up with the singer-songwriter Tuesday when he decided to busk on the street for the first time in 25 years ... belting out songs in the cold on the heels of venues canceling his shows.

Remember ... we spoke to Matis last week after his shows in Tucson, Arizona and Santa Fe, New Mexico were canceled because of last-minute safety concerns. Matisyahu was convinced both cancellations were the result of his views on the war in Gaza.

Clearly, Matis is tired of relying on venues and decided to take his music to the street ... saying he just wants to share his message of "love" with audiences.

Despite saying love's his purpose, Matisyahu admits he's also upset with the situation in the Middle East -- and his feelings of love quickly manifested into a diatribe on double standards.

Matis focused on the hostages in Gaza and slammed people who don't seem super concerned about them. He's got a theory on why this is ... chalking up the apathy to antisemitism.

Matisyahu fired off a list of other moments in history where Jewish people faced hardship and overcame ... before firing off the rallying cry, "We will f***ing win."

He followed all this up with a performance of "No Woman, No Cry" -- the hit song popularized by Bob Marley -- belting out the song with electric guitar accompaniment.