"Mazal Tov, 13-3-17, Abu Al-Hawa Ahmad."
Presumably Mr. Ahmad was getting married, or perhaps his son was. (I don't think it is a birth announcement because I saw this sign a few days ago before March 13.)
Jews are wishing a Mazal Tov to their Muslim co-worker.
And it is not the least bit strange - unless you get all your information about Israel from the mainstream media.