We ask living Christian believers to pray to God for us, so it is not wrong to ask those who have gone home to God to pray to God on our behalf as well.
From the distant past.
You probably missed this.
Ecclesiastes 9:5 For the living know that they shall die: but the dead know not any thing, neither have they any more a reward; for the memory of them is forgotten. 6 Also their love, and their hatred, and their envy, is now perished; neither have they any more a portion for ever in any thing that is done under the sun.
Wrong because we can ask other living on this planet believers to pray for us without having to do it through the spiritual realm. We can do it by means of physically talking to them, or writing them notes. We do not have to do it outside the physical realm.
Those whose bodies have died are not accessible by physical means, but must be contacted through spiritual means in the spiritual realm.
THAT is what we are forbidden to do.
Uh... they've gone NOWHERE except into the grave.
Else just WHO will be LEAVING their graves to meet Christ in the air??
1 Thessalonians 4:16
For the Lord himself will come down from heaven, with a loud command, with the voice of the archangel and with the trumpet call of God, and the dead in Christ will rise first.