"After having repeatedly examined my conscience before God, I have come to the certainty that my strengths due to an advanced age are no longer suited to an adequate exercise of the Petrine ministry, " he told the cardinals.

NPR: Pope Resigning On Feb. 28, Conclave In March

After having repeatedly examined my conscience before God, I have come to the certainty that my strengths, due to an advanced age, are no longer suited to an adequate exercise of the Petrine ministry.

CNN: Full text of Pope Benedict XVI's declaration

"After having repeatedly examined my conscience before God, I have come to the certainty that my strengths, due to an advanced age, are no longer suited to an adequate exercise of the Petrine Ministry, " he added.

WSJ: Pope Benedict XVI to Resign

"After having repeatedly examined my conscience before God, I have come to the certainty that my strengths, due to an advanced age, are no longer suited to an adequate exercise of the Petrine Ministry, " the pope said in a declaration in Latin to a gathering of cardinals on Monday.

WSJ: Pope Benedict XVI to Resign