A man stood on railings outside his parents' house and shouted "dirty knacker" after he left the scene of a family dispute, a court heard.
Laurence Venables (32) also made a threat to break windows at the house in a separate incident.
Venables, of Summerhill in the north inner city, pleaded guilty to threatening, abusive and insulting behaviour.
Judge Michael Walsh put him on a probation bond for a year.
Dublin District Court heard gardai were at the scene following a family dispute last May 25.
Venables agreed to leave the house but was arrested after jumping on to the railings and shouting: "See you, I'll get you, you dirty knacker."
He also threatened to break windows in the house after an argument with his parents on May 16.
His mother phoned the gardai, as she believed the threat would be carried out.
The court heard Venables was seen injecting heroin on Exchange Street in the city centre on July 27.
This was in full view of passers-by, and he became abusive and threatening towards gardai when confronted.