Ps 103:5

“"He hath founded the earth upon its firmness." He hath founded the Church upon the firmness of the Church. What is the firmness of the Church, but the foundation of the Church. What is the foundation of the Church, but that of which the Apostle saith, "Other foundation can no man lay but that is laid, which is Christ Jesus." And therefore, grounded on such a foundation, what hath she deserved to hear? "It shall not be bowed forever and ever." "He founded the earth on its firmness." That is, He hath founded the Church upon Christ the foundation. The Church will totter if the foundation totter; but when shall Christ totter, before whose coming unto us, and taking flesh on Him, "all things were made by Him, and without Him was not anything made;" who holdeth all things by His Majesty, and us by His goodness? Since Christ faileth not, "she shall not be bowed for ever and ever." Where are they who say that the Church hath perished from the world, when she cannot even be bowed. ...”

“And with regard to the earth it is again written in Job: He that hangeth the earth upon nothing; meaning, that it had nothing underneath it. And David in harmony with this, when he could discover nothing on which it was founded, says: He that hath founded the earth upon its own stability, as if he said, it hath been founded by thee upon itself, and not upon anything else.”