A Greek word meaning "appearance," "arrival," or "presence." Though it can be used of the arrival of any person, such as Paul's reporting of being comforted by the parousia of Titus at a time when he was facing a very difficult time in Macedonia (2 Cor 7:6-7) or of the the Philippian brethren's "obedience "not only in my presence (parousia), but now much more in my absence" (Phi 2:12), it is now almost always reserved for the day of Jesus's "second coming" (Matt 24:27, 37, 39; 1 Cor 15:23; 16:17; 1 Thess 2:19; 1 Jn 2:28).
Despite the many foolish attempts to predict the specific time of His return, Scriptures is adamant that it shall be
1) certain,
2) "sudden" and
3) its time and date: "No-one knows about that day or hour, not even the angels in heaven, nor the Son, but only the Father" (Matt 24:36).
Nor is there—despite the mantra being repeated ad nauseum, especially by American dispensationalist popularism—any biblical basis for the popular teaching that the Third Temple in Jerusalem must be rebuilt before our Lord returns. Whatever the temptations to give credence to such distracting teachings the proper response to this firm and certain hope is
1) to persevere in all that we go through as a result of our faith, and
2) to live everyday in such a manner that we shall not be caught unprepared at any time whatsoever.
In the scholarly study of this subject one of the issues that have attracted much attention is how to explain the apparent delay of the parousia. Jesus had spoken of the parousia as if it was imminent but, as the Christians addressed by Paul in 1 Thess shows, the delay of Jesus's coming seemed to have discouraged many of them to the point where they began to doubt if they had been taught right. For more on this see Bauckham's article listed below.
Resources:
Richard J. Bauckham, "The Delay of the Parousia," Tyndale Bulletin 31.1 (1980): 3-36. Pdf N
W. J. Grier, The Momentous Event. A discussion of Scripture teaching on the Second Advent. html 
This work may be three-quarters of a century old, and yet nothing in it is dated. In its examination of Scriptures regarding the Second Coming of our Lord Jesus Christ, it remains solid and steadfast despite so much that is publicity-grabbing that has been published since then. This book, to be sure, will continue to outlast many of those flimsy expositions that have made it to our bookshops in the last few decades.
©ALBERITH
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