In Malachi the Navi tells us (3:1): הנני שול ח מלאכי ופנה דר ך לפני ופתאום יבא אל היכלו האדון אשר אתם מבקשים ומלאך הברי ת אשר אתם חפצים. The Metzudos Dovid explains:האדון אשר אתם מבקשים – “The master which we are seeking”, refers to Moshiach who we are all eagerly waiting for (אשר עין כל אדם מצפה ומייחל לו ומב קש ביאתו), and: ומלאך הברית אשר אתם חפצים – “The angel of the covenant which we all desire”, refers to Eliyohu HaNavi, and that he should come and tell us about the final geulah [redemption] and techiyas hameisim [resurrection of the dead]. The pasuk adds: ופתאום יבא – “That he is going to arrive very suddenly”.
We see from the prophecy of Malachi that the arrival of Moshiach is going to happen very suddenly, and it can happen any second. Although, we have already waited many years and many deadlines for when he was supposed to arrive have passed, nonetheless, he can still come any second now. The question is, however, what exactly is the status of the obligation to anticipate his arrival (mezapeh liyeshuah)? Is it: בתור ת ודאי שיבא היום או רק בתורת ספק – “Something which we must anticipate will definitely happen today, or is it more of a doubt?”
