The Alter Rebbe writes beautifully about this in the end of Chapter 49 of the Tanya. The charity you have given throughout the year to various institutions and appeals has certainly contributed to both physical and spiritual light. Hashem will fulfill His promise: if you give tithes, you will be blessed with wealth.
https://www.torahrecordings.com/rebbe/igroskodesh/011/012/3800