Because that part would be theirs for ever. Every part belonged to a tribe, and could not be changed (Num. 36:9) from tribe to tribe:Command the children of Israel, and say unto them, When ye come into the land of Canaan; (this is the land that shall fall unto you for an inheritance, even the land of Canaan with the coasts thereof:)
A part could not be sold (Lev. 25:23) as well:Neither shall the inheritance remove from one tribe to another tribe; but every one of the tribes of the children of Israel shall keep himself to his own inheritance.
Everyone was legally allowed to buy his own land back (Lev. 25:27):The land shall not be sold for ever: for the land is mine; for ye are strangers and sojourners with me.
And when he did not have enough money, every fifty years the land would return (Lev. 25:28) to its original owner:Then let him count the years of the sale thereof, and restore the overplus unto the man to whom he sold it; that he may return unto his possession.
There is another reason why keeping track of genealogies was important. Both Jacob (Gen. 49) and Moses (Deut. 33) have blessed the different tribes. Every tribe got different blessings and different prophesies. But more important than those earthly promises, was the promise of the Messiah. Jacob prophesied (Gen. 49:10) that he would come forth from Juda:But if he be not able to restore it to him, then that which is sold shall remain in the hand of him that hath bought it until the year of jubile: and in the jubile it shall go out, and he shall return unto his possession.
Generally it is assumed that Chronicles was written by Ezra. This at a time when the Israelites returned from Bable, after a 70 year period of deportation. Is it strange that they scrupuously investigated each tribes genealogies again?The sceptre shall not depart from Judah, nor a lawgiver from between his feet, until Shiloh come; and unto him shall the gathering of the people be.
So the apostle must have something different in mind here. We find the answer in the previous verse, in 1 Tim. 1:3 where the apostle commanded Timotheus “that thou mightest charge some that they teach no other doctrine,” namely than I've thought you and what is found in the Scriptures. Ancient Jewish writings have been discovered, which delve into the most complex genealogies, connecting them with wild speculations about spiritual mysteries. So the apostle is saying that no other doctrine should be teached, no fables, no Jewish genealogies.Circumcised the eighth day, of the stock of Israel, of the tribe of Benjamin, an Hebrew of the Hebrews; as touching the law, a Pharisee;
That word 'endless' is 'aperantos' in the Greek meaning 'unfinished, (by implication) interminable' (Strong's no.562), and 'fables' is 'muthos' in the Greek meaning 'a tale, fiction, myth' (Strong's no.3454). The main subject there in 1 Timothy is the requirement of what subject matter is to be taught in God's Church, which is declared His Word, not man's traditions. Thus, 'fables' and 'endless genealogies' are referring to some preacher getting up at the pulpit and bringing in all kind of ficticous family analogies to teach with, instead of sticking to God's Word. The 'genealogies' God set forth in His Word are never a 'fable', or an 'endless genealogy', and any teacher that claims so is a false prophet that should not be heeded. God's genealogies are non-fiction, finite not endless, have a purpose, and are a part of His Word. So we must choose either to listen to man's words, staying ignorant of God's Word and His Plan, or we can choose to listen to our Father, The God of Abraham, The God of Isaac, and The God of Jacob.