In short
Jesus’ spiritual family is all who do his Father’s will (Matthew 12:50, Matthew 7:21). He does not mean doing instead of hearing (Matthew 7:24–29), but hearing leading to action (Luke 8:21).
The defining mark of those who belong to Jesus’ family is that they do the will of the Father (see Matthew 7:21). In Matthew 12:50 it is stressed that only those who actually live in accordance with the Father’s will have the right to be counted as members of Jesus’ family. The emphasis lies not on doing as opposed to hearing (cf. Matthew 7:24–29), but on a hearing that leads to action (see Luke 8:21).1
50 For whoever does the will of my Father in heaven is my brother and sister and mother.”