Matthew 6:1-2
"Be careful that you do not do your good deeds in front of people for the purpose of being seen by them, for [if you do] you will not have a reward from your Father in heaven.
Matthew 6:5
"And when you pray, do not be like the hypocrites who love to stand and pray in the synagogues and on street corners [i.e., in prominent view of everyone] in order to be seen [and praised] by people.
Matthew 6:16
"In addition, when you fast [i.e., go without food and/or drink for religious reasons], do not be like the hypocrites with long faces, for they go around with gloomy expressions on their faces in order to advertise that they are fasting. It is true when I say to you, these people have [already] received their reward.
Mark 14:4-5
But some [of the disciples. See Matt. 26:8] were upset among themselves, saying, "What is the reason for wasting this perfume?
Mark 14:37-38
And when He came back and found His disciples sleeping He said to Peter, "Simon, are you sleeping? Could you not stay alert [in prayer] for one hour?