'Rigor' in the Bible

And the Egyptians made the children of Israel to serve with rigor:

and they made their lives bitter with hard service, in mortar and in brick, and in all manner of service in the field, all their service, wherein they made them serve with rigor.

Thou shalt not rule over him with rigor, but shalt fear thy God.

And ye shall make them an inheritance for your children after you, to hold for a possession; of them shall ye take your bondmen for ever: but over your brethren the children of Israel ye shall not rule, one over another, with rigor.

As a servant hired year by year shall he be with him: he shall not rule with rigor over him in thy sight.

The diseased have ye not strengthened, neither have ye healed that which was sick, neither have ye bound up that which was broken, neither have ye brought back that which was driven away, neither have ye sought that which was lost; but with force and with rigor have ye ruled over them.