The victim, Omri Blum, was adopted by suspect Shai Blum and his wife almost 22 years ago.
The victim was transferred to Sha'are Zedek Medical Center in very serious and unstable condition for further medical treatment.
A 25-year-old man killed six and injured one at a kindergarten in China's Guangdong province on Monday, according to police.
Israel Police chief Kobi Shabtai arrived at the scene shortly after the incident.
Kobi Yekutiel was at the scene of the Tel Aviv terrorist attack, which saw nine people wounded. He recounted how he managed to shoot and kill the terrorist, and what he felt at the time.
Hamas spokesman Hazem Qassem praised the attack, saying that "The heroic attack in Tel Aviv is the first response to the occupation's crimes."
In response to his coworker's comment, the assailant grabbed a large knife and began striking and stabbing the victim in the head, body, and hands.