What is the role of ‘Eesa (peace be upon him)?


I would like to know what is the duties and functions of Jesus as "Al-Masih" in Islam. Many Christian anti-Islamic sites have been asking this question. Its not that my faith is not strong, but I could not explain my answer properly. Perhaps you can help me. 

Praise be to Allaah. 

‘Eesa (peace be upon him)
has two roles: 

His first role, which was before Allaah raised him up to heaven
when the Jews wanted to crucify him. His role at that time was, like
that of any other Prophet, to convey the Message. Allaah gave him the
Injeel (Gospel) to confirm the Tawraat (Torah), and He gave him miracles
which are well known, such as healing the blind and lepers, and raising
the dead by Allaah’s leave, and other well known miracles.

“He called his people to worship Allaah
Alone and to believe in Him alone (Tawheed), and he was a witness against
them throughout his stay among them.” 

His second role will come at the end of time, when the Dajjaal
will emerge. Allaah will send ‘Eesa down to the earth, and he will be
a leader of the believers who will rule them according to the Islamic
sharee’ah. He will kill the Dajjaal, and the Mahdi will appear during
his time. Blessings will come down from Allaah such that the milk of
one camel will be sufficient for a large number of people, and wealth
will be abundant. During his time Ya’jooj and Ma’jooj (Gog and Magog)
will emerge and will spread mischief throughout the earth. “Allaah will
destroy them and ‘Eesa (peace be upon him) will rule the earth according
to Islamic sharee’ah, until he dies and the Muslims offer the funeral
prayer for him.” Then Allaah will send a cool breeze which will take
the soul of every believer, and after that none will be left except
the most evil of people, upon whom the Hour will come.