Acts 1:20

For it is written in the book of Psalms, Let his habitation be made desolate, And let no man dwell therein: and, His office let another take.

The two passages from Psalms are Psalms 69:25 and Psalms 109:8, where certain unnamed enemies of the Psalmist are imprecated. Peter's reason for applying these words to Judas appears to be this: since the enemies of David, who was only a type of Christ, were thus denounced, then certainly an enemy and betrayer of the greater Son of David would be the proper object of the same denunciation.