“Then Jesus began
To say to them.
That no one
Leads you astray.’”
ὁ δὲ Ἰησοῦς ἤρξατο λέγειν αὐτοῖς Βλέπετε μή τις ὑμᾶς πλανήσῃ.
There is something similar in Matthew, chapter 24:4, and in Luke, chapter 21:8, almost word for word. Mark said that Jesus began to tell them about people who might lead them astray (ὁ δὲ Ἰησοῦς ἤρξατο λέγειν αὐτοῖς). He told them that they should be aware, so that they would not be led astray or be misled (Βλέπετε μή τις ὑμᾶς πλανήσῃ). They had to be cautious, so as not to be deceived.