Markus 9:42

9:42 “If anyone causes one of these little ones who believe in me to sin, it would be better for him to have a huge millstone ¹  tied around his neck and to be thrown into the sea.

Markus 11:25

11:25 Whenever you stand praying, if you have anything against anyone, forgive him, so that your Father in heaven will ²  also forgive you your sins.”

[9:42]  ¹ tn Grk “the millstone of a donkey.” This refers to a large flat stone turned by a donkey in the process of grinding grain (BDAG 661 s.v. μύλος 2; L&N 7.68-69). The same term is used in the parallel account in Matt 18:6.

[9:42]  sn The punishment of drowning with a heavy weight attached is extremely gruesome and reflects Jesus’ views concerning those who cause others who believe in him to sin.

[11:25]  ² tn Although the Greek subjunctive mood, formally required in a subordinate clause introduced by ἵνα ({ina), is traditionally translated by an English subjunctive (e.g., “may,” so KJV, NAB, NIV, NRSV), changes in the use of the subjunctive in English now result in most readers understanding such a statement as indicating permission (“may” = “has permission to”) or as indicating uncertainty (“may” = “might” or “may or may not”). Thus a number of more recent translations render such instances by an English future tense (“will,” so TEV, CEV, NLT, NASB 1995 update). That approach has been followed here.