Ans. The kingdom, in its present form, extends from Pentecost till the Lord comes for His saints.
There are many associations, both secular and religious, that might be spoken of as "bundles" of tares, but the wheat is mixed in with them. The wheat here is not Israel, but all who are the Lord's now; those who are cleansed from their sins and sealed by the Holy Spirit. When the Lord comes, He will gather them all into His granary. After that the angels will be called to do their work, (see verses 39, 41, 49).
The fishermen in verse 48 are the servants in the present time who understand what God is doing, not saving the world, but gathering out of it those who compose the body of Christ. They know that the gospel of the grace of God, that is preached now, gathers these only, and these are the good who believe the gospel to the salvation of their souls. The bad though, in the net, were only nominal Christians, that is, without being born again.
Ques. Is it right to say that the Father rested from the work of creation? Was not the Son the Creator?
Ans. In Gen. 1:11In the beginning God created the heaven and the earth. (Genesis 1:1) to 2:3, God is Elohim, a word that here stands for the whole Godhead, The Father, the Son, and the Holy Ghost.
In the work of creation, or in the work of redemption, all are engaged. It is the Father's will, the Son's work, and the Spirit's power and witness. While the Son, or the Word, is ever spoken of as the Creator, all are involved in what is done by Him. So in Gen. 2:33And God blessed the seventh day, and sanctified it: because that in it he had rested from all his work which God created and made. (Genesis 2:3) God rested, that is, the Father, Son, and the Holy Ghost, but when sin came in, that rest was broken. It is said by the Lord Jesus, in John 5:1717But Jesus answered them, My Father worketh hitherto, and I work. (John 5:17), "My Father worketh hitherto, and I work. Therefore the Jews sought to kill Him, because He not only had broken the Sabbath, but said also that God was His Father, making Himself equal with God.” In Him dwells all the fullness of the Godhead bodily. (Col. 2:99For in him dwelleth all the fulness of the Godhead bodily. (Colossians 2:9)). We are not slighting the Father, to say that the Son created all things. (Col. 1:15-1715Who is the image of the invisible God, the firstborn of every creature: 16For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him: 17And he is before all things, and by him all things consist. (Colossians 1:15‑17).) It is the best way to keep as close as we can to the language of Scripture.