Tradition
St. John Chrysostom
Homilies on First Corinthians
Homily 8 › 1 Corinthians 3:6
“I planted, Apollos watered, but God gave the increase.”
That is, I first cast the word into the ground; but, in order that the seeds might not wither away through temptations, Apollos added his own part. But the whole was of God.
Source: Homilies on First Corinthians (New Advent)