I understand.

In going through your daily life, look around and test yourself. 

You may be out of sympathy in regard to many thoughts and many opinions, but brushing that aside, can you say—

Although my viewpoint is different, I understand how they have come to their point of view?

Can you say frankly to the one concerned—

You and I do not look at things alike, but the affection is strong enough to make that barrier as nonexistent?

That is true brotherly love, that is the sister spirit. 

Looking at humanity as a whole, can you say—

I understand.