stocks - in which the prisoner’s feet were made fast until the time of execution (Jer 20:2).
lookest narrowly - as an overseer would watch a prisoner.
print - Either the stocks, or his disease, marked his soles (Hebrew, “roots”) as the bastinado would. Better, thou drawest (or diggest) [Gesenius] a line (or trench) [Gesenius] round my soles, beyond which I must not move [Umbreit].