In Christ's final week of life, Mary uses an entire year's salary worth of expensive oil to serve Christ. Upon realizing this, the apostles become upset with Mary because they feel that the oil could have been used for more worthy purposes like feeding the poor and needy. Judas, especially, is upset with Mary expresses these feelings of frustration toward her. Christ stands betwixt Mary and Judas' pointing finger when he responds, "Let her alone; against the day of my burying hath she kept this. For the poor always ye have with you; but me ye have not always," (v. 7-8). 

Judas does not take Christ's correction as Peter has done many times. He becomes bitter about the correction and either later that day or only a few days after, trades Christ for money. 

Often enough, we may respond to correction in  this manner. Especially when we feel that we are doing something right or worthy. However, Judas was completely missing the mark when he pointed out the faults of Mary. We can either chose to become bitter and offended when we are corrected or we can be more like Peter who was so willing to submit His will to Christ's and take the correction to change for the better.