Did the apostle Paul experience poverty after he became an apostle and did missionary work? Certain direct and indirect signals indicate that he did:
1) Paul speaks of "hardships" (ESV) that he and his coworkers faced: they recommended their ministry to others by arduous difficulties. In the same chapter of Corinthians, Paul describes himself and others "as sorrowful, yet always rejoicing; as poor, yet making many rich; as having nothing, yet possessing everything" (2 Corinthians 6:4-5, 10).
2) In 2 Corinthians 11:27, Paul confirms that he was often "in toil and hardship, through many a sleepless night, in hunger and thirst, often without food, in cold and exposure" (ESV).
Raymond Collins (Paideia Commentary on 2 Corinthians) offers these remarks:
"That Paul often lived with sleepless nights (see 6:5) and in hunger and thirst (cf. 1 Cor. 4:11, linking hunger and thirst) were probably consequences of his decision to be self-supporting. Manual laborers and artisans often did not make enough to feed themselves properly. Paul was often without food, in the cold, and poorly clothed. Paul’s being without food could be a reference to a religious fast, but in the context of a catalog of hardships, the expression more likely refers to the fact that Paul was hungry because he was poor (6:5). In 1 Cor. 4:11 Paul complains about being clad in rags (gymniteuomen, hapax in the NT). Now he says that he was poorly clothed (en gymnotēti; cf. Rom. 8:35), a sure sign of his poverty (cf. Epictetus, Diatr. 3.22.45). The verb and the noun denote nakedness, but those who were poorly clothed and in rags were said to be naked (cf. Seneca, Ben. 5.13.3). Before beginning the fool’s speech, Paul tells the Corinthians that despite being in poverty (11:9), he has refused to take any money from them. In the last several phrases of this long catalog of hardships, Paul spells out some of the consequences of his poverty"3) Paul relates some of his other hardships in Philippians 4:12-13 (NET): "I have experienced times of need and times of abundance. In any and every circumstance I have learned the secret of contentment, whether I go satisfied or hungry, have plenty or nothing. I am able to do all things through the one who strengthens me."
Compare Philippians 4:15-20.
4) An indirect proof that Paul lived in poverty as an apostle is 2 Corinthians 8:9 (ESV): "For you know the grace of our Lord Jesus Christ, that though he was rich, yet for your sake he became poor, so that you by his poverty might become rich."
Paul exhorted the Corinthians to imitate him even as he imitated Christ (1 Corinthians 11:1). Since Christ evidently became poor in a material sense, but made others rich through his poverty, might not Paul have followed the same course, especially in light of other verses in Corinthians? This seems like a genuine possibility to me.
Jan Lambrecht (Sacra Pagina Commentary on 2 Corinthians) points out that Christ became poor by assuming humanity (becoming human); however, Paul also likely had earthly poverty in mind when penning 2 Corinthians 8:9:
"Within Church history-and no less today-2 Cor 8:9 contains the appeal to fellowship with the poor Christ. How can a true Christian, how can the Church be rich or wealthy while the Lord became poor? A number of Christians have willingly become poor because of the poverty of Jesus and that of his poor brothers and sisters (cf. Matt 25:31-46). The preferential option for the poor is greatly stimulated by 2 Cor 8:9. However, the Christians' continuous struggle against all kinds of human misery and destitution shows that we must never exalt or idealize poverty as such."
Finally, another factor that lends credence to the apostle's self-imposed poverty is the form of a servant Christology that we find in Philippians 2:6-7. Although Christ existed in God's form, he took the form of a servant by becoming flesh. Being a servant implies that Christ had an unassuming status and that he practiced self-imposed poverty on earth: Paul urges the Philippians to have the same mind that Christ possessed.
Murphy O'Connor makes this observation on the poverty of Paul:
"In Paul’s time, as today, how you traveled depended on how much money you could afford to spend. Paul was not a rich man. The impression he gives in his letters is that he had no significant personal financial resources. He seems to have had nothing beyond what he could earn and the sporadic gifts sent to him by various churches (2 Corinthians 11:8–9; Philippians 4:14). As an itinerant artisan, a tent-maker (Acts 18:3), he was far better off than an unskilled worker of the laboring class, but no artisan became rich. It would have been as much as Paul could do to earn his daily bread, even if he had enjoyed a stable situation with a regular clientele. But Paul garnered much of his work from fellow travelers on the road, or he had to begin anew in a strange city where he had no reputation to attract business."
Collins, Raymond F. Second Corinthians. Paideia Series. Grand Rapids, MI: Baker Academic, 2013.
Lambrecht, Jan. Second Corinthians. Collegeville: The Liturgical Press, 1999. Print.
Murphy-O'Connor, Jerome. “On the Road and on the Sea with St. Paul.” Bible Review 1/2 (1985): 38–47.