The New Testament reveals that by the preaching of the gospel of Jesus Christ there were conversions to Christ of entire households.
Lydia – “And when she and her household were baptized, she begged us [Paul and Silas], saying, ‘If you have judged me to be faithful to the Lord, come to my house and stay.’” (Acts 16:15).
Jailer – “Then they [Paul and Silas] spoke the word of the Lord to him and to all who were in his house. And he took them the same hour of the night and washed their stripes. And immediately he and all his family were baptized” (Acts 16:32-33).
Stephanas & Crispus – “I [Paul] also baptized the household of Stephanas” (1 Cor 1:16). That happy event is recorded in the book of Acts. “Then Crispus, the ruler of the synagogue, believed on the Lord with all his household. And many of the Corinthians [including the household of Stephanas], hearing, believed and were baptized” (Acts 18:8).
These household conversions are suggested as a proof of infant baptism. Some insist that these households included infants and so infants must be baptized. However, the Greek word translated “household” means those who dwell in a house. Many of you reading this article are a part of a household in which there are no infants.
Who was actually converted in the instances above? Those whom the apostle judged to be faithful to the Lord. Those who understood the word of the Lord spoken to them. Those who were capable of believing on the Lord. And in each case their conversion to Christ was completed when they were baptized into Christ (Gal 3:27).