Albert Barnes on 1 Corinthians 7:8

To the unmarried. The word unmarried (αγαμοις) may refer either to those who had never been married, or to widowers. It here means simply those who were at that time unmarried, and his reasoning applies to both classes.

And widows. The apostle specifies these, though he had not specified widowers particularly. The reason of this distinction seems to be, that he considers more particularly the case of those females who had never been married, in the close of the chapter, 1Cor 7:25.

It is good for them. It may be advisable, in the present circumstances of persecution and distress, not to be encumbered with the cares and anxieties of a family. 1Cor 7:26,32-34.

If they abide. That they remain, in the present circumstances, unmarried. See 1Cor 7:26.

(*) "unmarried and widows" "Or to widowers"