John Gill Commentary Genesis 37:22

"And Reuben said unto them, Shed no blood; cast him into this pit that is in the wilderness, but lay no hand upon him: that he might deliver him out of their hand, to restore him to his father." — Genesis 37:22 (ASV)

And Reuben said unto them, shed no blood
Innocent blood, as the Targum of Jonathan; the blood of a man, a brother's blood, one that had not done anything wherefore it should be shed, and which would involve in guilt, and bring vengeance on them: he seems to put them in mind of the original law in (Genesis 9:6);

[but] cast him into this pit that [is] in the wilderness, and lay no
hand upon him :
which might seem to answer the same purpose, namely, by depriving him of his life in another way, by starving him; but this was not Reuben's intention, as appears by the next clause, and by his going to the pit afterwards, as it should seem, with a view to take him out of it privately; this advice he gave,

that he might rid him out of their hands, to deliver him to his father
again ;
safe and sound, in order, as it is thought by many interpreters, to reconcile his father to him, whose bed he had abused.