What are the main dispensations or ages in God’s plan?
Scripture reveals seven major dispensations, or periods of time in which God deals with His people in a distinct way: Innocence, Conscience, Human Government, Promise, Law, Grace and Truth, and finally the Millennium.
God works out His purpose in the earth through what is called dispensations, meaning a period of time along with the particular method by which God deals with His people during that time. Before Adam and Eve sinned, they lived under the Dispensation of Innocence, and God dealt with them accordingly. After the fall, and following the scattering of the people at the Tower of Babel, the Dispensation of Conscience began. From there the people were divided into nations, and God began dealing with them through human government.
Next came the Dispensation of Promise, given through Abraham. This was followed by the Dispensation of the Law, given to Moses. Then came the Dispensation of Grace and Truth, which came through Jesus Christ, and in which God now deals with His people by grace and truth rather than by the sacrifices and ordinances of the Law.
This present dispensation of Grace and Truth is also called the fullness of times, the Church Age, or the time of the Gentiles. Ephesians 1:10 speaks of the dispensation of the fullness of times, when God gathers together in one all things in Christ, both in heaven and on earth. Galatians 4:4-5 shows that in the fullness of time God sent forth His Son, made of a woman, made under the law, to redeem those under the law and to bring the adoption of sons. This dispensation of the Church will end when the Church is taken out.
The seventh and final dispensation named is the Millennium, which will be the last period in which God deals with mankind in this ordained sequence. Each dispensation carries its own method by which God reaches His people, and when the dispensation changes, God's method of dealing with His people changes as well.
The scriptures
For this cause I Paul, the prisoner of Jesus Christ for you Gentiles, If ye have heard of the dispensation of the grace of God which is given me to you-ward: How that by revelation he made known unto me the mystery; (as I wrote afore in few words,
God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets, Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds;
That in the dispensation of the fulness of times he might gather together in one all things in Christ, both which are in heaven, and which are on earth; even in him:
But when the fulness of the time was come, God sent forth his Son, made of a woman, made under the law, To redeem them that were under the law, that we might receive the adoption of sons.
From the books
This answer is drawn from these passages in the Mary Banks Faith Library.