Mark 1:1-11 narrates John's baptism and its heavenly origin, which Jesus directly references in his question.

Matthew 3 describes John's baptism and divine endorsement, providing the background for Jesus' question about its origin.

Luke 3 records John's baptism ministry and its authority from heaven, answering the question Jesus poses.

John 1:6 introduces John the Baptist as sent from God, supporting the heavenly origin of his baptism that Jesus asks about.

John 1:15-36 describes John the Baptist's testimony and baptism ministry, directly relevant to the 'baptism of John' Jesus asks about here.

In John 3:27, John states his ministry comes from heaven, directly answering Jesus' question about the origin of his baptism.

Matthew 14:5 shows the people regarded John as a prophet, explaining why the religious leaders feared to deny his divine origin.

John 3:27 directly says John can only receive from heaven, providing the explicit answer to whether his baptism is from heaven or men.