>I'm not sure if this would be cucked and I need someones opinion on this.
Alright.
>Do you think it would be cucked to have a good friend of mine ask her out sometime?
It highly depends.
> Basically I have this one friend who has his shit together a lot. He's about to start his career in engineering, he's smart, athletic and super religious.
All good things. However, make certain:
1.) He has the degree in engineering.
2.) Has started the job in engineering, and is actually pulling in a good income.
> He's been a best friend of mine for pretty much my whole life
Bonus points. Still, never trust a young man when it comes to sex. Life long male friends have been known to betray each other when it comes to women and sex. It is the weakest point in men.
>He's a bit of a white knight (this is the reason I would trust him with my sister) but a genuinely good guy who's always had good intentions with women as long as I've known him.
That's good.
>Would it be stupid to tell him to ask her out after high school is over?
"after high school" tells me likely does not have a degree in engineering yet nor a job in engineering. In such a case, I would say it would be stupid to have him date her.
Wait until he has the proven degree and/or the proven career income in place, first. That's critical.
>He's someone I would trust for her, and to hopefully marry her
Mentally place him on the potential list.
>but I'm not sure if that makes me a cuck
"Cuck" is a word that recently replaced "faggot" as the teenager term for a male that is submissive. It does not make you submissive to ensure your sister is married off to a man with a career. However, it would make you a fool to allow a man with no career to impregnate her. Trust me, it will be your family who pays a huge price if a jobless chad knocks your sister up. Your sister will have sex one way or the other someday. Making certain she is with a guy of social standing in no way makes you a "cuck".