'Unable' in the Bible

So we see that they were unable to enter because of unbelief.

Let us then, though we still have God's word that we may come into his rest, go in fear that some of you may be unable to do so.

For we do not have a high priest who is unable to sympathize with our weaknesses, but One who has been tested in every way as we are, yet without sin.

the which is an image for the present time, according to which both gifts and sacrifices, unable to perfect as to conscience him that worshipped, are offered,

For the law possesses a shadow of the good things to come but not the reality itself, and is therefore completely unable, by the same sacrifices offered continually, year after year, to perfect those who come to worship.