I think the Trinity can be understood perfectly clearly in a tangible way. It is the traditions of religion that have made it confusing.
Most can see that God is one, which is a profoundly essential truth to hold.
The Bible tells us we are made in
I will give children to be their princes,
And babes shall rule over them.
The people will be oppressed,
Every one by another and every one by his neighbor; The child will be insolent toward the elder,
And the base toward the honorable. (Isaiah 3: 4, 5 NKJ)
(In the statement below by Swedenborg the word 'remains' refers to innocence stored in the soul from childhood that allows a person to receive God).
Those who persuade themselves in regard to any subject,
confirm themselves in such persuasion
by everything which they imagine to be true,