The picture was fake — someone with image editing software added Trump onto the cross on the wall.
On July 19, 2022, TikTok user @mamasissiesays posted a video titled, "What Is Hanging in MTG's Office?" The clip showed what looked to be a picture of U.S. Rep. Marjorie Taylor Greene, R-Ga., reading the Bible in front of a figurine of former U.S. President Donald Trump hanging on a cross. The Trump figurine even appeared to be wearing a red MAGA hat. The caption read, "I beg of you, someone tell me it’s photoshopped." We're here to tell you that it is, indeed, a fake. Someone used image editing software, likely Adobe Photoshop, to add Trump on the cross.
According to help from TinEye reverse image search engine and the Wayback Machine on the Internet Archive, the original picture without Trump hanging on the cross was tweeted by Greene from her personal account on Nov. 13, 2021. That account has since been permanently suspended from the platform.
While Twitter did permanently suspend Greene's personal account, she still had a presence on the platform through her official representative account, @RepMTG.
In sum, no, the picture did not show a Trump figurine hanging on a cross on the wall behind Greene, as it had been doctored.