Is it permissible to lie to achieve personal interests or to avert harm, and is the prohibition of lying considered absolute or conditional in Islam?

Lying is fundamentally forbidden, but the Law has permitted it in situations where there is a predominant benefit, such as what came in the hadith of Umm Kulthum bint Uqba from the Prophet, peace and blessings be upon him: "He is not a liar who reconciles between people and says good things and promotes good." In a narration by Muslim: "And I did not hear him permit anything of what people call lies except in three: war, reconciling between people, and a man's conversation with his wife and a woman's conversation with her husband." The scholars have attached to this every praiseworthy objective that cannot be achieved except through lying. So, lying is permissible to achieve it if the objective is permissible, and it becomes obligatory if the objective is obligatory, while preferring equivocation whenever possible.