Matthew 6:2

Matthew 6:2. Therefore when thou doest thine alms, do not sound a trumpet before thee, as the hypocrites do in the synagogues and in the streets, that they may have glory of men. Verily I say unto you. They have their reward.

So that they will never have another. They have been paid once for it by the approbation of their fellow-men. They will never have any further reward.