If you are a US Citizen and are married to a non-US Citizen, you are entitled to petition on behalf of your spouse in order to get him/her an Immigrant Visa, which will lead to the Green Card. But once the petition is approved, you will have to demonstrate that you meet the US poverty guidelines, i.e. you have enough money to support him/her, and that you maintained a domicile in the US. For the revenue requirement, if you have not been working in the US, nor have properties in the country, you can use your assets abroad to demonstrate that you meet the poverty guidelines. But you will have to provide evidence of the source/legitimacy of those possessions and that you will (or already have) transfer the funds to the US.
Concerning the proof that you maintained a domicile in the US, you can fulfill this requirement by providing current US Bank account statements, tax returns, driver’s license, evidence of participation to elections.
If you didn’t maintain such ties with the US while you were living abroad, you will have to get a job offer, or even better secure employment and domicile in the US before filing for your spouse, in order to provide evidence of employment and current residence for at least three months before you file.
Of course, each case has to be assessed individually, and we strongly recommend that you seek advice from a Board Certified Immigration attorney in order to get appropriate guidance for your case!