I like the yoga one as you have coped well with the amount of text on there. It is still readable and I think the colours work nicely. The religious one I think the colours towards the top of the flyer are blending into the white too much. It is losing impact for me because of it. Hope that helps.
As I don't know how much of each of the flyers you've designed I'm just going to presume you've designed each element, logos and all for the sake of this post.
Balanced Life Yoga
I like the colours like Corrosive pointed out. The palette works fairly well and the textures help compliment it. However, the logo could do with some work and more thinking as it's a little "all over the place". There's no clear "look at this part first" or guidance around the logo, the same could be said for the flyer as a whole.
I'm also not sure about the stark block whites when surrounded by the muted brown palette. It's a little "woah" on the eyes, yet, it does give a bit of focus, I guess I'd play around with the layout a little more and see what you can do with that? I've always preferred vertical flyers as I think landscape feels a little unnatural, especially if there's a lot of content. It's always hard to get the layout faultless.
A few things about the font bugs me. Firstly, Radiant Yoga and the supporting text on the back of the flyer looks as if it's Papyrus? On a personal level, I hate that font. It doesn't look very professional and it reminds me of people who've just bought a computer and are making a poster in Microsoft Publisher. I just can't get away with it. That being said, if you're going to use it, I'd definitely only use it for heading and perhaps the subheadings as I think it's a fairly difficult font to read, especially when there's that much body copy, it could easily get messy. Definitely simplify the body copy if you have to keep Papyrus.
Remember too, that when you're printing that photograph on there to get it at the highest resolution possible as it looks a little grainy here.
I have to admit, I really like the "abstract" paint image, I think that works quite well. I think it's meant to be a cross, but, without looking at it for a bit longer than the average "flyer receiver" then, I don't think you'd get that from it. That could be owing the blending of the shape at the top. Again though, I quite like how it blends away to nothing. It has a kind of "spiritual/overbearing light" feel that I associate with religion so I don't think that should necessarily be removed.
Again for me, it's the font that lets you down. On the front, I think it looks fine, maybe the gradient cheapens it a little, but all in all that's not a bad effort. The back, I'd probably not use the same font in the body copy. It also looks as though you've stretched the font downover, something that shouldn't ever happen. If you haven't, then maybe just change the font for something a little less "cluttered feeling".
However, that cluttered feeling could be coming from the layout again. Is it necessary to have the painted cross on the back as well as the front? You've used it once already and in all honesty I think that's enough. If you lost it from the back, you'd gain some more space to work with, relieving the "crammed in in a hurry" feeling.
Sorry if all that seems overly harsh/critical or whatever, just trying to help.
Thank you both for the feedback, it is greatly appreciated.
In regards to the logo of the yoga one, I didn't create this, it was just given to me to use on it. I agree with what you're saying about it though Tony! Also as far as the picture is concerned.. The picture i was supplied with was ridiculously small, so I just put it on there to show what the overall flyer would look like as a whole until i received a bigger picture!