Can We Understand Spiritual Truths?

How well can we understand spiritual truths while we're on earth? When we try to understand one of the more complicated descriptions in the Heavenly Doctrines of how things work it becomes clear that there is a lot more going on then we are able to grasp and it can seem like spiritual truths are beyond us. However, in De Verbo 3:4 it says that Swedenborg was told that

there are not any Divine mysteries that cannot be perceived and expressed naturally also, even though more generally and less perfectly....

Doctrine of Faith 3 expresses a similar idea and assures us that we can understand spiritual truths and that, though they may not be clear, we can come to be able to tell whether a given idea is true or not. It also explains how it is possible for us to understand spiritual truths.

[It] is commonly said no one can comprehend spiritual, that is, theological matters because they are supernatural. Spiritual truths, however, are as capable of being comprehended as natural truths; and although the comprehension of them may not be clear, still when they are heard they fall so far within the perception of the hearer that he can discern whether they are truths or not; and this is especially the case with those who are affected by truths....

The reason that spiritual things can be comprehended is, because man as to his understanding is capable of being elevated into the light of heaven, in which light appear none but spiritual things which are truths of faith: for the light of heaven is spiritual light.