Depending on where a person is located at a given moment of time, he or she is viewed and treated as either a citizen or a foreigner.
And then there is the missionary.
True missionaries view themselves first and foremost as citizens of God's eternal kingdom which has neither borders nor geographical restrictions. They also have a home country which provides them with a passport and dear friends who pray and support their ministry. But missionaries also attempt to adapt to the country and culture of their calling.
A freshly caught fish flip-flops around on the bottom of the boat until it dies or is placed back into its own element. That may describe an American tourist abroad, but not a true missionary. The missionary feels at home in his country of origin and seeks this same state in the country where he lives and serves. The primary loyalty, however, is to the kingdom of God.
When people speak of missions, they do so from various standpoints. To the average church member, a missionary is a hero who makes great sacrifices to serve God and fellow man in a foreign country. The un-churched may view the missionary as someone who destroys primitive cultures, colonizes, or at best, "meddles" in other people's personal affairs. Missionaries themselves also have differing concepts of "missions" depending on their specific mission work. There are home and foreign missions, short term and career missions. Some missionaries work in the home office doing bookkeeping or they may go on the road to recruit workers. And there are the "tent-makers," a term that refers back to one of the earliest Christian missionaries, the Apostle Paul. He had learned to make tents as a youth and was employed as a tent maker in Corinth (Acts 18:1-3) to support his ministry there.
Nearly everyone sees missions as an objective undertaking while the "mission field" is viewed subjectively. The missionary is the giver or doer and the "mission field" is the needy recipient. I call this the "we and they; them and us" standpoint and it is not necessarily a biblical perspective. As a missionary serving in Europe, I learned much from my "mission field".
Our church recently conducted its annual mission conference with an emphasis on missions in Canada. Canadians are technically Americans, but they resent being classified as such. And they certainly do not consider themselves to be a mission field for US missionaries! Citizens of Quebec don't even like being called "French-speaking Canadians."
When Austrians asked us about our occupation, we always found ourselves in a dilemma. How should we answer? This may seem trivial to Americans, but it is not so simple when serving in foreign countries. If we replied, "We are missionaries" Austrians responded, "Oh that is nice; to what country?"
The Apostle Paul was a Roman citizen, a status which superseded national citizenship (Acts 22:24-30 and 23:27), but he only referred to this once and usually introduced himself as an Apostle (emissary) or a servant of Jesus Christ.
I was a carpenter before going to Austria, but could only claim that occupation in Austria if I was actually trained and accredited in Austria according to Austrian law. This means I would need to first become a carpenter's apprentice and then a journeyman before I could become recognized as a carpenter. If I continued in that trade for a defined length of time and passed state tests, I could become a "Master Carpenter" and own my own business.
Almost all nations (the USA may be the only exception) make distinct differences between citizens and foreigners. The differences are carefully documented in registrations, IDs, license tags etc. and the status is defined by law. All people are permitted certain freedoms such as breathing, eating, drinking, sleeping and shopping, but that is about the extent of equality. Both citizens and foreigners have free access to public places, even to streets and highways, provided they have a valid international driving permit and obey local traffic laws. If a police officer stops you for a traffic violation, you don't get off the hook by saying that you can't understand the language.
In Europe, foreigners can stay three months as tourists, but then they must obtain a residence visa and a national drivers license if they want to operate a vehicle. Without a valid visa you can't get a job, rent housing or enroll children in public school (home schooling is forbidden). Even after we obtained a residence visa, our kids had to pay to ride the school bus! There are no government entitlements (financial aid, socialized medical care etc.) for foreigners.
Foreigners without a residence visa cannot legally open a bank account. For many years Austrian banks offered anonymous savings accounts, similar to the well-known secret Swiss bank accounts. Although it was against the law for foreigners to own an anonymous bank account, many did because no identification was required. This was a boon for banks. Most owners of anonymous bank accounts had good (or evil) reasons to hide money in this manner. They hid it to avoid paying taxes or alimony. They hid it from their business partners, their offspring, spouse or from law enforcement officers. It was a convenient way to transfer large sums of money from drug deals and weapon sales. For these and other reasons, many owners of anonymous bank accounts kept the password secret. When they died or were killed, whoever got the book could collect its contents -- providing he or she knew the password. If the password is known only to the person lying in the casket, the bank wins. When Austria joined the European Union all that changed, but existing accounts were grandfathered in and Switzerland chose not to join the European Union.
America is unique among nations in that no registration is required. When foreigners come to America, they often have more liberties and entitlements than in their native country. In fact, they sometimes enjoy privileges denied US citizens!
We were in Austria long enough to obtain permanent documentation (our visas and drivers licenses are valid for life), but we are still considered foreigners and must register as such with the police should we decide to live in Austria.