According to Archbishop Lefebvre, Dom Marmion was one of the greatest masters of the spiritual life of our time.
He often encouraged priests, seminarians and the faithful to draw from his works and his spirituality, which can be summed up in the fundamental truth that all our perfection consists in expressing the image of Jesus Christ. God has predestined us to become similar to his Son.
From this principle Dom Marmion explains the role of Our Lady in our spiritual life:
“Now, in Jesus Christ there are attributes, perfections which are fundamental and essential, and others which flow from them and which we conceive as secondary.
“As far as the essential attributes are concerned, every Christian must reproduce them, and their perfection in each soul is the measure of its perfection, while the other attributes of Our Lord are reproduced more or less perfectly by souls according to the circumstances and the attraction of the Holy Ghost.
But there are two fundamental attributes which are, so to speak, the essence of the Man-God, and their imitation, their reproduction in us are the essence of our holiness: Jesus is ‘Filius Patris’ and ‘Filius Matris’. The more we will be ‘children of God’ and ‘children of Mary’ in Him, the more we will participate in His infinite holiness, the more perfect we will be.
“It is through baptism, by clothing ourselves with Jesus Christ, that we necessarily become in Him, the children of the eternal Father and the children of His Mother.”
Dom Marmion insists that this is not a pious exaggeration or something fictitious: it is not a figure, a metaphor.
“As St. John says: ‘it is not only in name, but in reality, that we become children of God’ (1 St. John 3:1).
“In the same way, we are truly children of Mary because she is the Mother of His mystical body. On the cross, Jesus officially entrusted us to His Mother, because if she gave birth to her unblemished child in joy, it was in pain that she had to give birth to sinners.”
Hence our duty to live fully according to this grace of adoption by filling our hearts with the dispositions of Jesus Christ towards His Mother:
“Jesus being essentially ‘Son of God’ and ‘Son of Mary’, we too must be by grace what Jesus Christ is by nature: children of God and children of Mary. God will only recognise for His true sons those who, like Jesus, are children of Mary.”
The whole approach of the Christian in his relationship with Mary will therefore consist in modelling himself on the most intimate feelings of Jesus towards His Mother: “Jesus Christ is our model. And just as we find in Him the perfect type of the child of God, in Him we will also find the perfect type of the child of Mary.”
The invocation freely chosen by Don Marmion and which he constantly repeated was: “Mater Christi”. He saw Mary above all as the Mother of Christ, and he himself wanted to be another son, “another Christ” for Mary.