I know of a couple of places where Baha'u'llah mentions the concept of a person being inwardly and outwardly united.
"No two men can be found who may be said to be outwardly and inwardly united. The evidences of discord and malice are apparent everywhere, though all were made for harmony and union." Gleanings, CXII
"Perhaps they [the divine friends] will visit the illumined beauty of the pure, radiant and sanctified friend in the land of love, detachment, amiability and exaltation. Thus would they receive the lights dawning from the morn of his brow and the effulgence of the perspicuous day, to at least the extent that they would be enabled to unite their inner and outer selves... Now, they must put forth their utmost effort and give their unswerving attention, so that their inward secrets not be contrary to their overt behavior, nor their outward deeds at variance with their inner mysteries." Tablet of the Holy Mariner - Persian section
In Tablet of the Son, Baha'u'llah explains that what's unique to the Baha'i revelation is the appearance of 'virtue'. Yes, virtue has appeared before in previous dispensations, but in this dispensation, it has been given a new importance:
"Note that what appeared was virtues, of which all remained ignorant. It would be the indisputable truth to say that all of these virtues were hidden and concealed in the scriptures and that in the dispensation of the Point of the Bayan, the veiled faces of meaning came out from behind the curtain in the chambers of the divine verses. And if it were said that what went before was a concise mention, whereas thereafter came one who clarified and spoke in detail, that would be the truth, in which there is not doubt. If it were said that what became manifest in the new revelation had not been apparent in previous dispensations - though all are wondrous and new - this saying is also correct and complete." Tablet of the Son, para 8
Other places where I've seen Baha'u'llh underlining this theme about virtue is in the Hidden Words:
"O MY FRIENDS! Quench ye the lamp of error, and kindle within your hearts the everlasting torch of divine guidance. For ere long the assayers of mankind shall, in the holy presence of the Adored, accept naught but purest virtue and deeds of stainless holiness." Persian Hidden Words, no 35
"O CHILDREN OF ADAM! Holy words and pure and goodly deeds ascend unto the heaven of celestial glory. Strive that your deeds may be cleansed from the dust of self and hypocrisy and find favor at the court of glory; for ere long the assayers of mankind shall, in the holy presence of the Adored One, accept naught but absolute virtue and deeds of stainless purity. This is the day-star of wisdom and of divine mystery that hath shone above the horizon of the divine will. Blessed are they that turn thereunto." Persian Hidden Words, no 69
And let's not forget the all-important first passage of the Aqdas, which states that our deeds must be consistent with our claims to faith:
"The first duty prescribed by God for His servants is the recognition of Him Who is the Dayspring of His Revelation and the Fountain of His laws, Who representeth the Godhead in both the Kingdom of His Cause and the world of creation. Whoso achieveth this duty hath attained unto all good; and whoso is deprived thereof hath gone astray, though he be the author of every righteous deed. It behoveth everyone who reacheth this most sublime station, this summit of transcendent glory, to observe every ordinance of Him Who is the Desire of the world. These twin duties are inseparable. Neither is acceptable without the other. Thus hath it been decreed by Him Who is the Source of Divine inspiration."
My understanding of the above quotes is this: that in the Baha'i revelation, the unity of our inner and outer selves is crucial. Hypocrisy is rejected and those who are motivated by it will find themselves powerless to achieve their purposes. There is no excuse any more, we must truly purify our inner and outer selves of all but God.
Why am I mentioning this? When the US was planning to invade Iraq, I argued that the whole thing was folly because George Bush and his allies were hypocrites. They talked about democracy, freedom and so on, but only thought of these universal goods for the people in their own priviledged countries. They didn't act with the principle of the oneness of humanity in their hearts. And I believe from the above quotes that Baha'u'llah has rendered hypocrites powerless in this Day. No matter what resources they throw at it, they can't achieve their purpose.
The principle of inner and outer unity also came to my mind in a related context - the business of the gunman who shot the students and staff at Virginia Tech University. The details that have surfaced about the gunman show that, on the inside, the guy had an inner life dominated by violence. And it's clear to everyone that this inner life lead to him killing people. But, as a society, we tend to downplay the importance of our inner lives and their effect on our outer lives. We allow violent video games, violent movies, and images of violent crime and war to flood our lives and yet reject the idea this might have any impact on our outer lives. In general, people would be hard pressed to take seriously Baha'u'llah's call to purify our inner selves of all that stuff.
The Virginia massacre also got me thinking about the way the 'war on terror' has been conceptualised. What is the source of terror? Generally, it is thought to be people who 'hate our freedoms', or who have genuine grievances against the West, or who have a different cultural and religious background to those in the West and feel their own way of life is threatened. Critics have pointed out that the US is a terrorist state. Those on the receiving end of the Iraq invasion couldn't help but be terrified. After all, it was called 'shock and awe' for a reason. But it seems to me that the source of terror isn't a group of people from any particular religion or culture; it's our inner selves. That's the source of terror. If we don't have inner selves dominated by feelings of hatred and images of violence, then we won't kill people.
What struck me about the video footage of the gunman - and it was no doubt not lost on anyone else - was the amount he'd learned from terrorist groups that had filmed murder of hostages and posted it on the Internet. Authorities appear to have rejected the idea that the massacre was a terrorist attack, but is that the right conclusion? The gunman is as much a terrorist as anyone blowing things up in Baghdad. A 'terrorist' is a universal phenomenon; it's any person with a sense of grievance and an inner life crazy enough to inspire massacre. What's to stop people everywhere with a grievance from rising up and causing havoc?
If we want to 'save' ourselves from 'terrorists', then we need to focus on the principle Baha'u'llah has set for us. We need to start by cleaning up our own inner lives, not by accusing others of being evil and assuming ourselves to be lily white. And we need to create a society with citizens that don't ever think about violent things.