Soli Deo Gloria is a fancy Latin phrase that means "To God alone be the glory." It's like saying that God deserves all the credit and praise for everything good that happens. Kind of like when your teacher gives you a sticker for being really good at something, it's like saying that God deserves all the stickers for being awesome. People who say Soli Deo Gloria believe that everything good we do or have comes from God and so we should thank and honor Him for it. It's like saying thank you to your parents for giving you nice things, but instead of parents, it's like saying thank you to God for all the good things in life.