The Pulpit Commentary - Mark 8:15
Beware of the leaven of the Pharisees and the leaven of Herod. St. Matthew ( Matthew 15:6 ) says, "Beware of the leaven of the Pharisees and Sadducees;" thus St. Mark identifies the leaven of the Sadducees with that of Herod. "Leaven" here means "doctrine." They were not to beware of this, so far as the Pharisees rightly taught and explained the Law of Moses; but only so far as they corrupted that Law by their own vain traditions, contrary to the Law of God, St. Luke ( Luke 12:11 )... read more
The Pulpit Commentary - Mark 8:14-21
Leaven. After the great miracle of the feeding of the four thousand, Jesus "entered into a boat with his disciples, and came."—for rest, probably—"into the parts of Dalmanutha. And they forgot to take bread." Had not emphasis been laid on their forgetfulness, we might have supposed they had been led to think "one loaf" enough; for if the Master could feed four thousand with seven loaves, surely he could feed twelve men with one! These men were yet but children in understanding, and... read more