Next-generation cosmological surveys will offer an unprecedented opportunity to test the nature of gravity on large scales. One method of doing so is via the statistic known as EG, which combines weak lensing, galaxy clustering, and redshift-space distortion measurements. I will discuss an investigation into the theoretical uncertainty of EG. I will then present theoretical predictions for EG under modifications to General Relativity. Finally, I will explore prospects for testing gravity using EG and future surveys.