Contradiction with Matthew 24:42
Mark 13:36 warns against sleeping and being unprepared for the master's return, while Matthew 24:42 emphasizes the vigilance required because the hour is unknown, suggesting ongoing alertness rather than the suddenness.
Matthew 24:42: Watch therefore: for ye know not what hour your Lord doth come.
Contradiction with 1 Thessalonians 5:2-3
Mark 13:36 implies sudden surprise, whereas 1 Thessalonians 5:2-3 describes an unexpected, inescapable destruction as a thief in the night, not just about alertness but about the certainty of unanticipated timing.
1 Thessalonians 5:2-3: For yourselves know perfectly that the day of the Lord so cometh as a thief in the night.
Contradiction with Luke 12:40
Mark 13:36 emphasizes readiness due to lack of knowledge of timing, but Luke 12:40 focuses on the certainty of the Son of Man's coming, seeming more on inevitability rather than sudden unpreparedness.
Luke 12:40: Be ye therefore ready also: for the Son of man cometh at an hour when ye think not.