Justin Bieber made headlines this Father's Day with a fierce declaration that he’s a father not to be trifled with.

In a striking black-and-white selfie posted on Instagram, the 31-year-old pop sensation wrote, "I’m a dad that’s not to be f***ed with 💪🏼," signaling his fierce protective instincts.

The post garnered an enthusiastic reaction from his wife, Hailey Bieber, who showed her support with a like.

Fans chimed in with their thoughts, with one person expressing concern over Justin's well-being, stating, "I love you so much and I’m so worried about you, king." Others praised his assertiveness, with a fan noting, "This is a man that’s standing on business."

Critics, however, didn't hold back, with some suggesting that the singer, who welcomed his son Jack Blues with Hailey in August 2024, seemed to be under the influence.

Bieber's intense mood seems to reflect his protective fatherly instincts, which he showcased again while dealing with paparazzi outside Soho House Malibu.

"Not me today bro. How do you think it’s going with you in my f***ing face? Get out of my f***ing face!" he snapped at the photographers trying to get a reaction.

Continuing to assert his boundaries, he added, "I’m a real man with a real family... I’m not to be f***ed with by any of you."

Frustrated by the overwhelming media attention, Justin expressed, "I’m at my wit’s f***ing end is what I am at," anticipating that the paparazzi would twist his words.

The very next day, he reiterated his strong parental stance by sharing heartwarming photos of himself with his son, captioned with more playful defiance, including a middle finger emoji.

Giiving the public a peek into his life as a new father, Bieber is clearly embracing his role while not shying away from defending his family fiercely.