“Jacob’s Ladder in freemasonry point to the connection between earth and heaven; between man and God; and represent faith in God, charity towards all men and hope in immortality.

The Masonic square was found in many temples, and also appears in the great pyramid. 

It is said that it was used symbolical­ly for squaring conduct, perfecting of the personality. To build on the square was to build for ever, according to the teachings of ancient Egypt; and in the Egyptian Hall of Judge­ment Osiris is seen seated on the square while judging the dead.

Thus in the macrocosm, the square came to symbolize the foundation of eternal law, that reflected in the four bodies of man; and the columns – were the symbols of the aspects of the law: Osiris, Father ; Isis – feminine aspect; and Horus – the as a star of Monad – at the culmination of the ladder.

The two pillars at initiation, there supposed to stand at the entrance to the other world, and the various experiences through which the candidate passed were intended to symbolize those which would come to him when he passed out of this physical world into the next stage. 

In the Lodge room is symbolized a temple of humanity, and as such it may be taken to symbolize a man lying upon his back.

The three powers of consciousness appearing in man as the spiritual will, the intuitional love and the higher intelligence, which are the root of all human will, love and thought.

The three columns, as a divine aspects, representing wisdom, strength and beauty, were stated to stand round God’s throne, which was the altar itself, which signify love.

Divine Trinity of Father, Son and Holy Ghost, or Shiva, Vishnu and Brahma are one Universal God in whom everything exists, whether it be animate or inanimate, for there is nothing but That.

But in Their separate appearances, the Holy Ghost is the maker or builder of the outer world, – objectivity; and the Son is the life in all beings, the “light that lighteth every man that cometh into the world”- subjectivity.

Both the Holy Ghost and the Son are in turn triune as their interplay produces energy:

(1) the visible world of material objects; Mother;

(2) the invisible energy with which the world is filled, and on which all things that are seen are built – this is the strength of God the Holy Ghost;

(3) the universal mind, the world of ideas, the storehouse of archetypes -Son. 

These are the three parts of any objective world; they constitute the Lodge, the building, – the field of consciousness, as it has been called in the Bhagavad Gita.

The pillars also represent once more the two great laws of progress, karma and dharma, the former providing the environment or material world, and the latter the direction of the self within – “ the ladder”; by the union or harmonious working of these two laws a man may attain the stability and strength required for the occult path to become a blazing Star.

From  C. W. Leadbeater –  Hidden Life In Freemasonry