The Corinthians had written a letter to the apostle Paul letter, which has not survived. It was never intended by God to be part of the inspired canon, though it was no doubt an inspired letter.
If we are unmarried, the Lord will sustain, and the Lord will mightily bless. So the apostle insists upon the unmarried state as also a noble state to be in, one which may be so blessed of the Lord.
Although touching is a euphemism for marriage, at the same time it is literally true and wise. Be careful of modern culture. The considerable degree of touching in society is a relatively new thing. In days gone by a man did not touch a woman, except maybe to shake her hand. But in this fallen and debased culture, considerable touching across the sexes outside marriage has become almost the norm – touching and hugging and feeling. While this is spoken of marriage, the phrase is literally true. It is indelicate, impolite, bordering on the coarse; it is overfamiliar, unwise, to be touching across the sexes outside of marriage.