I understand that those who practice praying to the saints rely heavily on either their own experience in this regard or on the experience of others who likewise practiced praying to the saints in their lives. However, they may also have some support from the Bible for this practice. What places from the Bible do such Christians view as indicating the validity of this practice?
So, this is what DRV suggest. (all Bible quotes in RSV)
Moses and Samuel can intercede:
Then the LORD said to me, "Though Moses and Samuel stood before me, yet my heart would not turn toward this people. Send them out of my sight, and let them go! (Jer. 15:1)
Jeremiah does intercede:
This is a man who loves the brethren and prays much for the people and the holy city, Jeremiah, the prophet of God. (2 Macc. 15:14)
Further Raphael hears and intercedes:
And so, when you and your daughter-in-law Sarah prayed, I brought a reminder of your prayer before the Holy One; and when you buried the dead, I was likewise present with you. (Tobit 12:12)
(There are misc. references in Revelation of John to saints praying in heaven, the DRV references this:
And when he had taken the scroll, the four living creatures and the twenty-four elders fell down before the Lamb, each holding a harp, and with golden bowls full of incense, which are the prayers of the saints; (Rev. 5:8)
The efficacy of these prayers can be seen:
And the LORD appeared to him the same night and said, "I am the God of Abraham your father; fear not, for I am with you and will bless you and multiply your descendants for my servant Abraham's sake."
I don't really see that much which needs to be expounded on after that.