1 Corinthians 7: 7 I added the parenthesis and note.
I wish that all men were as I am (single). But each man has his own gift from God; one has this gift, another has that.
Verse 28
But if you do marry, you have not sinned; and if a virgin marries, she has not sinned. But those who marry will face many troubles in this life, and I want to spare you this
Verses 32-35
I would like you to be free from concern. An unmarried man is concerned about the Lord's affairs--how he can please the Lord. But a married man is concerned about the affairs of this world--how he can please his wife-- and his interests are divided. An unmarried woman or virgin is concerned about the Lord's affairs: Her aim is to be devoted to the Lord in both body and spirit. But a married woman is concerned about the affairs of this world--how she can please her husband. I am saying this for your own good, not to restrict you, but that you may live in a right way in undivided devotion to the Lord.
Read all of 1 Corinthians 7, and you will understand how a person can be fully devoted to ministry as a single person. This is not to say that they cannot minister when married, because they can, but they are not as free to do so because his interests are divided between his God and his wife.