The Mahdi and Prophet Jesus (pbuh)
Imam Rabbani states that the Mahdi will come 1,000 years after our Prophet's (may God bless him and grant him peace) death, within 2000s:
"It is expected that, after 1,000 years, this secret administration will be renovated. It will be granted with superiority... This way, genuine virtue will emerge and cover the degradation... And it is expected that the Mahdi, the supporter, will come. May God be pleased with him." (Imam Rabbani, Letters of Rabbani, vol. 1, p. 569)
The confirmation of the religious law, the renovation of people takes place in this second thousand. The just witnesses of the truthfulness of this cause are the existence of Prophet Jesus [pbuh] and Mahdi in this period (the second thousand years). (Imam Rabbani, Letters of Rabbani, vol. 1, p. 611)
Those among the nation of Allah's Messenger (may God bless him and grant him peace) are highly perfected in faith. It does not matter whether they are few in number, even a thousand years passes after the death of our Prophet (may God bless him and grant him peace). Their being perfected in faith serves to the following end: strenghtening the Islamic law in its true sense.
The coming of the Mahdi after 1,000 years serves this purpose. Our Prophet (may God bless him and grant him peace), the last Messenger, gave the glad tidings of his coming. Prophet Jesus (pbuh), on the other hand, will come down after 1,000 years. (Imam Rabbani, Letters of Rabbani, vol. 1, p. 440)
A little more than 1,000 years pass over the passing of God's Messenger (may God bless him and grant him peace) from this life, a time comes and the true Islam rises from its own ranks and unites with the truth of the Ka`bah. Then, on behalf of the true Islam, the name of truth of Ahmad emerges... From the two names comes a name into effect; and the place of true Islam is left unoccupied until the coming of Prophet Jesus [pbuh]. Ultimately, Prophet Jesus [pbuh] comes and performs his religious duties in conformity with the religious laws of Islam. Then, true Christianity rises from its own ranks and rules in the realms of true Islam. (Imam Rabbani, Letters of Rabbani, vol. 1, p. 470)
A thousand years after the death of our Prophet (may God bless him and grant him peace), people will enter the second millennium. According to Imam Rabbani, quoted above, the Mahdi and Prophet Jesus (pbuh) will come during that time.
Jalal ad-Din as-Suyuti wrote that:
The life of this community will exceed 1,000 years, yet be limited to 1,500 years. (Muhammad ibn `Abd ar-Rasul Barzanji, Al-Isha`ah li Ashrat as-Sa`ah, p. 299)
Thus, as-Suyuti draws attention to Hijri 1000-1500, during which some glad tidings (e.g., the Mahdi's appearance, Prophet Jesus' (pbuh) second coming, and the prevalence of Islam's morality) will come true. We are now in the fifteenth Islamic century. Thus Prophet Jesus' (pbuh) return is very near. (God knows best)
Bediuzzaman Said Nursi also confirms this glad tiding and calls attention to the events that will take place until Hijri 1506:
"The first statement, with reference to 1500, indicates the last times of those who struggle for religion in the End Times; the second statement, with reference to 1506 calls attention to the date of the victorious struggle. (...) until this date (1506), it hints that it will, evidently and clearly, continue in a victorious manner." (Sikke-i Tasdik-i Gayb, p. 46)