Mark 3:21

3:21 When his family ¹  heard this they went out to restrain him, for they said, “He is out of his mind.”

Mark 12:12

12:12 Now ²  they wanted to arrest him (but they feared the crowd), because they realized that he told this parable against them. So ³  they left him and went away. ⁴ 

[3:21]  ¹ tc Western witnesses D W it, instead of reading οἱ παρ᾿ αὐτοῦ (Joi par’ aujtou, here translated “family”), have περὶ αὐτοῦ οἱ γραμματεῖς καὶ οἱ λοιποί (peri autou Joi grammatei" kai Joi loipoi, “[when] the scribes and others [heard] about him”). But this reading is obviously motivated, for it removes the embarrassing statement about Jesus’ family’s opinion of him as “out of his mind” and transfers this view to the Lord’s opponents. The fact that virtually all other witnesses have οἱ παρ᾿ αὐτοῦ here, coupled with the strong internal evidence for the shorter reading, shows this Western reading to be secondary.

[12:12]  ² tn Here καί (kai) has been translated as “now” to introduce a somewhat parenthetical remark by the author.

[12:12]  ³ tn Here καί (kai) has been translated as “so” to indicate the implied result of previous action(s) in the narrative.

[12:12]  ⁴ sn The point of the parable in Mark 12:1-12 is that the leaders of the nation have been rejected by God and the vineyard (v. 9, referring to the nation and its privileged status) will be taken from them and given to others (an allusion to the Gentiles).