I started a game as the Chinese, emperor level, standard terra map. I fell behind quickly and was dead last out of 8 civs. I also was beaten to all the early religions so I didn't have a state religion. Slowly 3 religions spread into some of my cities. I noticed that the top two civs both had Judaism. They were not close to me and I had open borders with both of them, so they were already +2 favorable towards me. I decided to take Judaism as my state religion. I immediately got a another +2. So the top two civs liked me a lot. At first I just did it because I thought they would be less likely to attack me, but then I "asked" for some techs for free and they just gave them to me. To qualify this, they were not any modern techs for the era, the new techs I was researching were in the low thousands in beakers and the techs I asked for were around 200-400, but still, I got 3 free techs that would of cost me around 1,000-1,500 coin. I haven't tried to get any more pricey techs yet.