In Catholicism, what scripture canon supports intercessory prayers from the dead? What are arguments against it?

Only use evidence from the canon and historical writing from the father's of the faith in the first few centuries that also used scripture canon, not including the apocrypha. The evidence I've seen put forward does not provide substantial evidence that anyone but the Holy Spirit and Christ interceed on our behalf. Or, used evidence contrary to the Catholic faith to support the contrary argument that praying to the saints, to Mary etc. is not supported by cannon, nor by early writing pre-nicea. I hope this question makes sense. I know I am ignorant in this regard and have read the Catholic arguments that appear very weak to me.