While Israel was chosen on the basis of God’s love, there was purpose and reason to Israel’s election.
A key purpose is stated at the outset of God’s revelation at Mount Sinai in Exodus 19:6:
‘… and ye shall be unto me a kingdom of priests, and a holy nation.’
Israel’s status as a holy nation was based on her election. A purpose of the election was for Israel to be a kingdom of priests. While Israel had a priestly tribe, the Tribe of Levi, the nation as a whole was also to be a priesthood. The historical function of a priest was to represent man to God. The Tribe of Levi represented Israel before God; and Israel was to represent the Gentile nations before God. This was perhaps the primary purpose of Israel’s national election and all other reasons are subservient to this one.
A second reason was to be the recipient of God’s revelation and to record it. For this reason, Israel received the Law of Moses (Deut. 4:5-8; 6:6-9; Rom. 3:1-2).
A third reason was to propagate the doctrine of the One God in Isaiah 43:10-12:
Ye are my witnesses, saith Jehovah, and my servant whom I have chosen; that ye may know and believe me, and understand that I am he: before me there was no God formed, neither shall there be after me. I, even I, am Jehovah; and besides me there is no saviour. I have declared, and I have saved, and I have showed; and there was no strange god among you: therefore ye are my witnesses, saith Jehovah, and I am God. In this passage, Israel was chosen to proclaim to the Gentile nations two things: first, that Jehovah, the God of Israel, is the only God; and, second, He is the only Savior and all who seek salvation must find it in Him.
A fourth reason was to produce the Messiah (Rom. 9:5; Heb. 2:16-17; 7:13-14).”
Excerpt From: Arnold G. Fruchtenbaum. “Israelology: The Missing Link in Systematic Theology.”Also in ePub (iPad) and Mobi (Kindle) formats.