'Sufficient' in the Bible

"Can a human being be useful to God, since he, who is wise, is sufficient to himself?

“Though his children are many, they are destined for the sword;And his descendants will not have sufficient bread.

“Why do you complain against Him?That He does not answer [you with] all His doings.

“Will your wealth [be sufficient to] keep you from [the confinement of] distress,Or will all the force of your strength do it?