This is an ingame prop of the 10 Commandments, two ancient stone tablets. 

(This is actually one .ydr file, the tablet has different writing on both sides, so if you flip one it looks like two tablets.) 

Install:

1) Download and install Add-On Prop mod

https://www.gta5-mods.com/tools/addonprops

>make sure you have openiv, Menyoo, and AddonPeds

https://www.gta5-mods.com/tools/openiv

https://www.gta5-mods.com/scripts/menyoo-pc-sp

https://www.gta5-mods.com/scripts/addonpeds-asi-pedselector

2) In OpenIV, While in Edit Mode, Put each included .YDR file into the props folder

OpenIV/GTA V/mods/update/x64/dlcpacks/addonprops

3)Go to GTAV folder, right click on propeditor.exe and select Run as Administrator

4)once inside addon Props Editor:

>click Prop tab at the top

>add prop(manual), 

make sure to name the prop the same as the ydr file (in this case "ten")

>set Textures to Embedded

>set LodDist to 500

>set Flags to 32

>click Add Prop

5)Click Rebuild at the top, when it completes click OK

6)A folder will popup, place the "def_prop.ytyp" file from that folder into the addonprops folder in 

/dlcpacks/addonprops 

Done! Now you can load the prop ingame manually, using Menyoo or another trainer of your choice. 

credits: 

free 3d model by dazinbane on devientart, 

https://www.deviantart.com/dazinbane/art/Ten-Commandments-Freebie-897740919

conversion by Snowie and NotOfTheWorld