“Amen” is translated as “truth,” “verity,” and expresses our inner agreement, the inner decision, to do some action with all our strength.
Therefore, the people are obliged to say “Amen” before the entrance to the land of Israel. This is an agreement with those conditions without which they can’t enter, because to enter means to rise to the correction of completely new egoistic desires and intentions that are now being revealed.
At every stage the people repeat “Amen” because every time they enter into a completely new correction.
From KabTV’s “Secrets of the Eternal Book” 11/21/16