Vincent's NT Word Studies
26. His words (rhmatov). Singular number. Rev., properly, saying. See on ch. i. 37.27-40. Compare Matt. xxii. 23-33; Mark xii. 18-27.
Robertson's NT Word Studies
20:26 {They were not able} (ouk iscusan). They did not have strength. An old verb iscuw from iscus (strength). They failed "to take hold (cf. verse #20) of the saying before the people." These "crack" students had made an ignominious failure and were not able to make a case for the surrender of Jesus to Pilate. He had slipped through their net with the utmost ease. {Held their peace} (esigesan). Ingressive aorist active of sigaw. They became silent as they went back with the "dry grins."