Does a believer’s faith save the rest of the household?

Neither passage says that one person’s faith saves another. In Acts 16 the promise to the jailer’s household was the same promise made to him, and it reached them the same way. Luke goes straight on: “they spake unto him the word of the Lord, and to all that were in his house” (16:32), and the evening ends with the jailer “believing in God with all his house” (16:34). The household heard the gospel and, like him, believed. The promise was that the same salvation was offered to them, not that his faith would stand in for theirs.

In 1 Corinthians 7 Paul does not say the unbelieving husband is saved, but “sanctified” (hēgiastai, ‘made holy’ or ‘set apart’). The Corinthians were asking whether a Christian married to an unbeliever was defiled by the marriage and should leave. Paul answers that the marriage is not unclean: the believer’s presence sets the home apart, and so “now are they holy”, the children too. That is not the same as being forgiven and born again, which is why Paul can add in verse 16 that the believing wife cannot know whether she will in the end ‘save’ (win to faith) her husband. So the passages agree: a believer’s faith blesses the home and opens the way for the gospel there, but each member must believe for himself.

A lawful marriage

John Gill noted that in Jewish usage, in the Mishnah and Talmud, a man who betroths a wife is said to ‘sanctify’ her (Hebrew qiddesh). He read Paul as saying that the mixed marriage is a true and lawful marriage, so that the children are legitimate, not that the unbeliever is made holy within.

Households and baptism

Catholic, Orthodox, Lutheran, Reformed and Anglican Christians point to household baptisms (Acts 16:15, 33) and to the holiness of believers’ children (1 Corinthians 7:14) in support of baptising the infants of believers. Reformed writers speak of such children as within the covenant community, though not thereby assured of salvation. Baptists and others hold that only those who can themselves believe should be baptised, and note that the jailer’s household heard the word and believed (Acts 16:32, 34).

What exactly Paul means by ‘sanctified’ and ‘holy’ in 1 Corinthians 7:14 is debated. Some read it of a marriage made lawful and clean in God’s eyes, others of a home placed under godly influence and within reach of God’s grace.