Mohammed Abbkr was found guilty on Monday by majority 11-1 verdicts of trying to kill Hashi Odowa, 82, and Mohammed Rayaz, 70, in February and March this year.
Abbkr was on trial for two weeks at Birmingham Crown Court, which heard he had been diagnosed with paranoid schizophrenia.
“I swear in the name of Allah, in the name of God, you will know me,” he told his first victim.
Jurors deliberated for more than seven hours over two days before returning guilty verdicts, having been asked to consider whether Abbkr should be found not guilty by reason of insanity.
The trial was told that he used a lighter and petrol in a water bottle to set fire to Mr Odowa and Mr Rayaz on February 27 and March 20.
Abbkr, who came to the UK from Sudan in 2017 seeking asylum and was granted leave to remain two years later, denied two counts of attempted murder and two alternative counts of maliciously administering a destructive thing to endanger life.
The 29-year-old, of Gillott Road, Edgbaston, was assisted in the dock by an Arabic interpreter as he was found guilty.
Mr Odowa suffered minor burn injuries to his ear and hand after being set on fire as he made his way to a neighbour’s car outside the West Ealing Islamic Centre in west London.
Mr Rayaz suffered serious burn injuries, particularly to his head, in Shenstone Road, Edgbaston, and was treated in hospital for a number of weeks.
CCTV footage of both attacks was shown to jurors during the trial.
Prosecutor Nicholas de la Poer KC told the jury that Abbkr had attended prayers at the West Ealing Islamic Centre before following Mr Odowa.
“There followed a conversation during which the defendant insisted that Mr Odowa knew him. Mr Odowa told the defendant that he did not,” Mr de la Poer added.
“The defendant said, ‘I swear in the name of Allah, in the name of God, you will know me’.
“Having sprayed Mr Odowa with petrol, the defendant drew out a lighter, struck the lighter, held it to Mr Odowa’s neck and ignited the petrol.”
Abbkr walked away from the scene and despite media appeals was only tracked down a day after attacking Mr Rayaz, who was a regular worshipper at Birmingham’s Dudley Road Mosque.
Mr Rayaz was followed for more than five minutes after leaving the mosque’s prayer hall, with CCTV footage showing Abbkr within feet of him as they passed a Caribbean food store on Dudley Road.
Abbkr was seen to take a clear plastic bottle from a rucksack, approach Mr Rayaz, placed a hand on his shoulder and ask him if he spoke Arabic.
“The defendant then sprayed Mr Rayaz with the petrol. Using a lighter, the defendant set fire to the petrol. Mr Rayaz was engulfed in flame,” Mr de la Poer told the jury.
The court was told that, as the initial flare of the fire began to diminish, the defendant threw more petrol from his bottle on to the flames and they “grew in size and intensity once again”.
In a statement issued by West Midlands, Mohammed Ayaz, the eldest son of Mr Rayaz, said: “Seeing my father on the evening of 20th March in the burnt state he was in was just an awful and unbearable thing to see.
“No words can describe that moment the emotions which I was feeling, I felt so helpless and weak; no son or daughter should see their father or mother in that state.”
Another of his sons, Adnaan Riaz, said: “Seeing the CCTV video of my dad being set on fire, his screams of pain and then reliving the visuals to the build-up of the attack and then after the attack will be with me forever.
“I would describe the attacker as a coward, this coward does not belong to any religion, society or even humanity.
“This impact of emotions which I have shared with you will be felt by me and my family for a very long time to come, and will remain with me for the rest of my life.”
Chief Inspector Haroon Chughtai, of Birmingham Police, said: “These were absolutely horrific attacks which almost defy belief in their apparent randomness and severity.
“Counter-terrorism officers were initially called in to investigate, given the nature of the attacks. While they have continued the investigation, we have found no evidence that Abbkr was motivated by a particular ideology and so this has not been treated as a terrorist attack.
“Thankfully these kinds of attacks are incredibly rare, but in the aftermath we worked closely with mosques around Birmingham to offer reassurance and listen to their concerns.
“The courage of the victims and their families has been exceptional. They have been left with physical and emotional wounds that they may never recover from, but I hope today’s verdicts will offer them some comfort.”
Adjourning the case, the recorder of Birmingham Melbourne Inman KC told the court that he wanted to hear further psychiatric evidence before considering a proposal to sentence Abbkr to a hospital order.
Abbkr was remanded in custody until a sentencing hearing on November 17.