And we are witnesses (kai hmei marture). Compare "ye yourselves know" (verse John 37 ). Peter thus appeals to what the audience know and to what the disciples know. He made the same claim about personal witnesses of the Resurrection of Jesus at Pentecost ( John 2:32 ). Here Peter affirms full knowledge of the work of Jesus in Judea (for whole country including Galilee and Perea) and Jerusalem (given mainly in John's Gospel). In the Greek wn (which) is attracted into the genitive case to agree with the antecedent pantwn (all), a common enough idiom. Whom also they slew (on kai aneilan). Second aorist active indicative of anairew with a as often in Acts ( John 2:23 ; John 5:30 ). But note kai (also) in the old MSS., not in the Textus Receptus. They "also" slew him, went that far, "this crowning atrocity" (Vincent), kai could here be "even." Hanging him on a tree (kremasante epi xulou). This same expression used by Peter in John 5:30 which see for discussion.