hope: confident, forward-looking expectation of a good outcome
In everyday English, to hope for something is to want an outcome you are not sure of. The word the New Testament uses for hope usually means something much firmer. It is a settled, forward-looking confidence that what God has promised will actually come, so it stands closer to assurance than to wishing. Its usual focus is the future God has pledged: the resurrection of the dead, salvation, eternal life, and the return of Christ.
This confidence was not the ordinary flavor of the Greek word. In older Greek, hope was a gamble. It could mean a good expectation or a dread of coming evil, and Greek writers often treated it as a comforter that misleads people in danger. The New Testament writers, drawing on the Old Testament, filled the same word with a different content: hope now rests on God's faithfulness rather than on the odds, which is why it can be spoken of as sure.
The word works at two levels, and the New Testament moves easily between them. Sometimes it names the inner attitude, the act of hoping and the confidence a person holds. Other times it names the thing being hoped for, the promised future treated as a single object, as when believers lay hold of their hope or have a hope kept safe for them in heaven. These are two sides of one expectation: the hoping, and the good that is hoped for. A few times the word keeps its plain everyday sense, an ordinary expectation of gain or of a good result, with no religious weight.
Because this hope is anchored in God's own promise (ἐπαγγελία), the New Testament can call it secure and even already given, while its full arrival is still awaited. That is why hope stands beside faith (πίστις) and love as one of the three lasting marks of the Christian life.