Matthew 16:6

16:6 Then Jesus said unto them, Take heed and beware of the leaven of the Pharisees and of the Sadducees.

Mark 8:15

8:15 And he charged them, saying, Take heed, beware of the leaven of the Pharisees, and [of] the leaven of Herod.

Luke 11:35

11:35 Take heed therefore that the light which is in thee be not darkness.

Luke 12:1

12:1 In the mean time, when there were gathered together an innumerable multitude of people, insomuch that they trode one upon another, he began to say unto his disciples first of all, Beware ye of the leaven of the Pharisees, which is hypocrisy.

Luke 12:15

12:15 And he said unto them, Take heed, and beware of covetousness: for a man’s life consisteth not in the abundance of the things which he possesseth.

Hebrews 2:1

2:1 Therefore we ought to give the more earnest heed to the things which we have heard, lest at any time we should let [them] slip.