Catholic
The Catholic Church teaches that the saints in heaven intercede for the living, and that Christians may ask for their prayers, since all are united in the communion of saints. It holds that such intercession in no way detracts from Christ, the one mediator, but manifests his power at work in his members.
Source: CCC 956; 2683 ↗
Orthodox
The Orthodox Church teaches that the saints — and above all the Theotokos — intercede before God for the living, and that asking their prayers is a natural expression of the Church's unity across death. It holds that the whole Church, militant and triumphant, worships and intercedes together.
Source: The Orthodox Faith, Vol. II ↗
Lutheran
Lutherans teach that the saints in heaven pray for the Church, and that their example may be honored — but that Scripture gives no command or promise for invoking them. They hold that Christ alone is our mediator and intercessor, and that prayer is to be directed to God through him.
Source: Apology of the Augsburg Confession, Art. XXI ↗
Reformed
The Reformed tradition teaches that Christ alone is the mediator and intercessor between God and man, ever living to make intercession for his people. It holds that prayer is to be made to God through Christ by the Spirit, and that invoking saints or angels has no warrant in Scripture.
Source: Westminster Confession 8.8; 21.2–21.3 ↗
Baptist
Baptists teach that Jesus Christ is the one mediator between God and man, now exalted at the Father's right hand where he intercedes for believers. They hold that Christians pray directly to God through Christ, and that as consistent Baptist practice no saint or angel is invoked as intercessor.
Source: BFM 2000, II.B ↗
Methodist
Methodists teach that Christ is the sole mediator and intercessor, through whom all prayer is offered to the Father. They hold that believers also intercede for one another in mutual prayer, but that invocation of the departed saints is not part of Methodist devotion.
Source: Articles of Religion, Art. XIV; UMC What We Believe ↗