"I find … that released under conditions without modifications that he does pose a danger," Jackson said after a dramatic hearing in U.S. District Court in Washington, D.C., that she scheduled a day after Stone's post Monday on Instagram.
"Roger Stone fully understands the power of words and the power of symbols," she said. "In this age of social media there's really no such thing as a takeback."
"Publicity cannot subside if it's the defendant that's fanning the flames," said Jackson, who added that Stone's apology rang hollow.
"I'm not convinced that Mr. Stone is all talk and no action," she said in reference to what she said could be seen as a threat to her safety from the post. "There's nothing ambiguous about a crosshairs."
Stone earlier had said on the witness stand, "I am hurtfully sorry for my own stupidity." He said nothing to reporters and members of the public as he left court.
Stone was arrested in January on charges of witness tampering, obstruction of justice and making false statements to Congress. The charges are tied to his alleged efforts to have the document disclosure group WikiLeaks release emails stolen from Democrats by Russian intelligence agents, including Hillary Clinton's campaign chairman, during the 2016 campaign.
Stone has pleaded not guilty in the case.
Jackson last week had issued a partial gag order that barred Stone, 66, and his lawyers from making any statements that could prejudice the case against him.
But just three days later, Stone posted the Jackson photo on Instagram, which called her "an Obama appointed Judge who dismissed the Benghazi charges against Hillary Clinton."
Stone's lawyers argued his partial gag order should be maintained. A lawyer for Mueller's office said it should be stiffened, arguing that his testimony about the post and his apology were "not credible."
Jackson's updated order essentially takes away Stone's ability to decide for himself what may or may not be a prejudicial statement about his case by barring him from saying anything at all about it.
Jackson on Thursday said: "So no, Mr. Stone, I'm not giving you another chance. I have serious doubts on whether you learned any lesson at all."
And she implied that the next time Stone crosses her it will lead to her revoking his bond and sending him to jail
The judge was clear that this is his last chance before jail.
Last June, Jackson revoked the bond of Stone's former lobbying partner, Paul Manafort, after he was accused by Mueller of trying to tamper with witnesses in his own criminal case. Manafort, who has been in jail since then, is awaiting sentencing next month for multiple crimes.
"Today, I gave you a second chance," Jackson told Stone. "This is not baseball, you don't get a third chance."
Earlier Thursday, Stone testified about what led to the Instagram photo of the judge being posted.
"It was an egregious, stupid mistake," Stone said of the photo, which he quickly took down Monday after it drew attention.
Stone had testified that a volunteer who worked for him posted the photo of Jackson next to the crosshair, but that he actually put it online and wrote the accompanying text about Jackson. That text criticized the fact that Jackson was specifically assigned to his case, instead of a judge who was randomly assigned.
Jackson's assignment stems from the fact that she was already presiding over another criminal case that involves evidence seized with a search warrant that was related to Stone's case.
"It was thoughtless," Stone said of his post.
"I am kicking myself not as much as my wife is kicking me."
"I let myself down, my family down, my attorneys down," he said. "It was a momentary lapse of judgement. I heard political commentators talking about the likelihood that I'll be raped in prison. It's been a stressful situation."
"My consulting business has dried up. I've exhausted my savings. I'm being treated for emotional distress," Stone said.
"I'm having a hard time putting food on the table and making rent."
Stone said, "I honestly didn't believe" the image next to Jackson's face "were crosshairs."
Stone also said he had not noticed what he described as a "celtic cross" in the corner of the image shared on Instagram.
"I didn't recognize it as a crosshairs," he said.
The "bad judgment," he said, was possibly "borne of the emotional stress of the situation" surrounding his criminal case.
"And I took it down because I recognized it could be misinterpreted," he said.
Stone's lawyer Bruce Rogow, in arguing that the original gag order should not be changed, admitted that the Instagram post was "indefensible."
"I agree with you there," said Jackson, whose displeasure with Stone's actions was clear during the hearing.
"You told me not to worry and that the media attention would subside," Jackson told Rogow.
"He has insisted that his name be in the paper every day since then. So on what basis would that forecast be believable?" Jackson asked the lawyer. "What would get him to stop talking other than a court order?"
The Instagram post was taken down soon after it drew attention Monday, and Stone and his lawyers apologized for it in a court filing later that same night.
But Jackson on Tuesday ordered Stone to appear in her courtroom Thursday to explain why she should not either tighten a partial gag order she had imposed on him, or modify or even revoke his release bond.
Before he arrived at court Thursday, Stone made several posts on Instagram about his legal fight.
Stone made another religious reference on the witness stand Thursday.
"Forgive me this trespass," he said.