30 those who mourn, as if they did not; those who are happy, as if they were not; those who buy something, as if it were not theirs to keep;

Read 1 Corinthians 7:30 Using Other Translations

And they that weep, as though they wept not; and they that rejoice, as though they rejoiced not; and they that buy, as though they possessed not;
and those who mourn as though they were not mourning, and those who rejoice as though they were not rejoicing, and those who buy as though they had no goods,
Those who weep or who rejoice or who buy things should not be absorbed by their weeping or their joy or their possessions.