How Long Will It Last?

Chasam Sofer cites Rabbeinu Bachya that the length of duration of the first and second Beis Hamikdash is alluded to in the beginning of this parsha. The opening verse states that these are the accountings of ‘the Mishkan’ the ‘Mishkan of Testimony.’ The words ‘the Mishkan’ in Hebrew is one word ‘HaMishkan’ which using ‘Gematriya’ the numerical equivalent of the Hebrew letters equals 415 and since there are five letters in that word that total sum is 420, the span of time of the second Beis Hamikdash.