invite someone with complete sincerity 三顾茅庐

“三顾茅庐”，汉语成语，字面意思是“pay three visits to the thatched cottage”，原为刘备拜访诸葛亮的故事。后人用“三顾茅庐”来比喻诚心实意地一再邀请。可以翻译为“invite someone with complete sincerity，repeatedly request somebody to take up a post”。

例句：

我们三顾茅庐才请到老先生做我们的学术顾问。

Only at our earnest and repeated requests did the old scholar agree to be our academic councilor.