Where an accused commits unprovoked assault using a lethal weapon (knife) causing serious bodily harm that interferes with the victim's health (particularly life-threatening injuries such as penetrating chest wounds with potential internal organ damage), a custodial sentence is warranted and invariably imposed unless there are substantial mitigatory factors such as provocation or pregnancy. A fine, even if accompanied by a wholly suspended sentence, is manifestly inadequate and not in accordance with real and substantial justice in such circumstances. The degree of force or violence used, the nature of the weapon, the seriousness of injury, persistent and unprovoked nature of the assault, and medical evidence of harm must be given proper weight in sentencing. The fact that an accused is a first offender, pleaded guilty, is employed, and has family responsibilities does not outweigh these serious aggravating factors so as to justify a non-custodial sentence.