It is mentioned in 61:11 surah As-Saf. What does it really mean to strive with wealth and lives? Does it mean to make more wealth and give it in charity? Does it mean to strive and struggle in general?
That you believe in Allah and His Messenger, and that you strive hard and fight in the cause of Allah with your wealth and your lives, that will be better for you, if you but know!) this is better than the trade of this life and striving hard for it and amassing it.
He also quoted an indication for a hadith where the sahaba asked the Messenger of Allah about the deeds Allah likes best. Among them was jihad and striving with wealth and lives means: That one needs money to buy armor to either to go and fight or to help the Muslim army with some "material" and supplies, so spending money for this cause for a believer has a (slightly) higher degree than fighting, as this is what striving with lives means. (See also this hadith which seems to be the reason for the revelation for surat as-Saff (61)).
As the main objective of surat as-Saff is about following the call to arms and obedience if Allah's Messenger calls or asks believers to do so the primary meaning of wealth here is spending for an army that is going out to fight for the sake of Allah and the meaning of struggling with lives is to go out and fight the enemies. So there's no relation to charity nor to strive and struggle in general in the context of this verse.