Charles Ellicott Commentary Isaiah 58:9

"Then shalt thou call, and Jehovah will answer; thou shalt cry, and he will say, Here I am. If thou take away from the midst of thee the yoke, the putting forth of the finger, and speaking wickedly;" — Isaiah 58:9 (ASV)

Then you will call. —The words point to the secret of the prayer which is answered, in contrast to the formal worship that found no acceptance (Isaiah 58:2; Isaiah 58:4).

The putting forth of the finger. —The gesture (Cheyne compares the “infamis digitus” of Persius ii. 33) has in nearly all nations been a natural symbol of scorn. It is in action what the words Raca and You fool are in the language of Matthew 5:22.