אַשְׁרֵ֥י הַֽמְחַכֶּ֖ה וְיַגִּ֑יעַ לְיָמִ֕ים אֶ֕לֶף שְׁלֹ֥שׁ מֵא֖וֹת שְׁלֹשִׁ֥ים וַחֲמִשָּֽׁה׃
װױל צו דעם װאָס האַרט און װעט דערגרײכן ביז טױזנט דרײַ הונדערט און פֿינף און דרײַסיק טעג.
Rashi
Fortunate is he who waits etc. Forty five years are added to the above number, for our King Messiah is destined to be hidden after he is revealed and to be revealed again. So we find in Midrash Ruth, and so did Rabbi Eleazar HaKalir establish (in the concluding poem of the morning service of the portion dealing with the month of Nissan): “and he will be concealed from them six weeks of years.”