Exegesis:

diarēxas tous chitōnas autou ‘tearing his (own) garments.’

diarēssō (only here in Mark) ‘rend,’ ‘burst,’ ‘tear.’

hoi chitōnes (cf. 6.9) ‘the tunics’: as Arndt & Gingrich remark the word is here probably used in a general way for ‘clothes,’ ‘garments,’ rather than strictly with reference to the under-garments (the parallel Mt. 26.65 has ta himatia ‘the garments’). Revised Standard Version ‘mantle’ is inaccurate: cf. ‘clothes’ (Moffatt, Williams, Translator’s New Testament, American Standard Version), ‘vestments’ (Montgomery), ‘garments’ (The Modern Speech New Testament, Manson), ‘clothing’ (Goodspeed). The gesture of tearing one’s garments was indicative of sorrow or horror and in the case of judicial proceedings, such as this one, in tearing his garments the high priest indulged in a formal ceremonial act, minutely prescribed by tradition.

chreian echomen (cf. 2.17) ‘we have need of.’

marturōn (only here in Mark) ‘witnesses.’

Translation:

For high priest see 14.47.

Tore must not imply some accidental tearing, but a deliberate, planned tearing as a gesture of consummate indignation. Such an action may not be readily understandable to people in other cultures but the context is such as to prevent any very wrong interpretation of the action.

Mantle should be translated by the most generic term for ‘clothes.’

Still need witnesses is equivalent in some languages to ‘need more people to speak against him’ or ‘require more men to say what they know about him.’

Quoted with permission from Bratcher, Robert G. and Nida, Eugene A. A Handbook on the Gospel of Mark. (UBS Handbook Series). New York: UBS, 1961. For this and other handbooks for translators see here .