It's a subtle-body thing - a feeling energetic quality.
Iranians feel. They're deep, authentic, and warm. They're embodied and sensual, even though they're modest and humble. They communicate their hearts in countless big and little ways all the time.
One way this comes across is the way Persian people often greet each other. They put their hands over their hearts and briefly bow their heads. And when they do this, they don't just go through the motions. Their subtle bodies exude a humble sweet warmth that really lets you know they're opening their hearts to you. The essence is in the sincerity. It looks a little like this:
Evidently, this form of greeting goes way back into the dim recesses of Persian history - back even before Islam came to Iran - back to Zoroastrian, or even pre-Zoroastrian days. Persians have greeted each other this way for millenia.
Maybe this greeting dates way back to when Cyrus (the first great Persian Emperor) conquered Babylon and, instead of slaughtering, enslaving, and raping everyone, he freed the many slaves (including many Jews) and guaranteed everyone freedom of religion - many historians have called this the first historical charter of human rights!