He must have been talking with Bergoglio.
“A number of miracle stories turn out in the light of form criticism to be projections of the experiences of Easter back into the earthly life of Jesus, or anticipatory representations of the exalted Christ. Among these epiphany stories we should probably include the stilling of the storm, the transfiguration, Jesus’ walking on the lake, the feeding of the four (or five) thousand and the miraculous draught of fishes. The clear purpose of the stories of the raising from the dead of Jairus’s daughter, the widow’s son at Naim and Lazarus is to present Jesus as Lord over life and death. It is the nature miracles which turn out to be secondary accretions to the original tradition.
“The result of all this is that we must describe many of the gospel miracle stories as legendary. Legends of this sort should be examined less for their historical than for their theological content. They say something, not about individual facts of saving history, but about the single saving event which is Jesus Christ. To show that certain miracles cannot be ascribed to the earthly Jesus does not mean that they have no theological or kerygmatic significance…The probability is that we need not take the so-called ‘nature miracles’ as historical.” (Jesus the Christ, p. 90-91)
Cardinal Kasper is referred to as "Pope Francis' theologian".
Here is what Francis has said about Cardinal Kasper, ""Yesterday, before going to sleep - although I did not do this to put myself to sleep - I read or rather re-read the work of Cardinal Kasper, and I would like to thank him because I found profound theology, and even serene thinking in theology. It is pleasant to read serene theology. And I also found what Saint Ignatius told us about, that 'sensus Ecclesiae," love for Mother Church. It did me good and an idea came to me - excuse me, Eminence, if I embarrass you - but the idea is that this is called 'doing theology on one's knees.' Thank you. Thank you." Bergolio later followed up Kasper's theology with his heretical Amoris Latitiae.