Small tidbits and Sparks of wisdom

The relationship between God and Israel, established through the giving of the Law by God and its acceptance by Israel — is the context within which the significance of the Tabernacle as a whole and in its parts is to be sought and found. This significance explains why the chapters on the construction of the Tabernacle follow the chapters containing the fundamental principles of the Law and the covenant established on the basis of the Law.
If the construction of the מקדש־משכן is considered from this perspective, the materials to be donated for this construction signify the factors through which the consecration of life is to be realized, and the factors by which God’s sanctifying and blessed closeness is to be recognized. For it is from God that we first received these materials, with which we are to demonstrate our devotion to God, and by donating them we will get them back with a twofold blessing. As Yaakov said, when he laid the cornerstone and first foundation for the first House of God: וכל אשר תתן לי עשר אעשרנו לך (Bereshis 28:22). King David, when preparing for the building of the First Temple, expressed the same idea even more explicitly: כי ממך הכל ומידך נתנו לך (Divrei Ha-Yamim I, 29:14).
And just now the people were made aware of this idea — most succinctly but comprehensively — by the throwing of half of the blood of the covenant onto the altar and half toward the people (above, 24:6 and 8).
In Collected Writings, vol. III, pp. 169–173, Rabbi Samson Raphael Hirsch zt”l showed that metals, because of their hardness, appear in תנ״ך as metaphors for firmness and strength (e.g., Yirmeyahu 1:18; Iyov 6:12; Yeshayahu 48:4). Because of their value, they appear as symbols of the value attached to spiritual assets (e.g., Mishlei 2:4; Tehillim 19:11; Iyov 28). But especially because of their metallurgical properties, they appear as symbols of all that is good and true in “alloys” containing various degrees of evil and falsehood, and as metaphors for the process of testing and refinement associated with truth and morality (e.g., Iyov 23:10; Zecharyah 13:9; Malachi 3:3; Mishlei 17:3; Yeshayahu 48:10; Mishlei 25:4; 10:20; 26:23; Yirmeyahu 6:29–30; Tehillim 119:119; Yechezkel 22:18; Yeshayahu 1:22; Daniyel 2:32–33). In all these passages, metals symbolize various degrees of moral purity and truth. Copper represents an ignoble nature, not yet refined. Silver signifies the stage of requiring purification and being amenable to refinement. Gold, which is usually found in unalloyed form and which can withstand the most rigorous tests, is a symbol of the purest and most refined moral nobility and of true and unfailing constancy.

This is the model for life.
Giving something back to Hashem from what He first gave you is not charity in the ordinary sense. It is recognition of reality. Nothing is truly yours. Your life was given to you. You did not purchase yourself. You did not create yourself. You did not design your mind, your talents, your health, your family, or the opportunities placed before you. Someone placed you on the trajectory that allowed you to receive what you now possess.
Whether a person is blessed with a brilliant mind, significant wealth, inherited assets, strong health, or even just the simple daily necessities that sustain ordinary life — all of it is a gift from God.
Truma and tzedakah are not losses. They are acknowledgments. They declare: “This was never mine to begin with.”
And that is why Rabbi Samson Raphael Hirsch zt”l speaks of a twofold blessing. When a person gives from what was entrusted to him, he receives it back refined. Elevated. Strengthened. Just as metals are purified through fire, so too a person’s possessions and abilities become purified through proper giving.
כי ממך הכל ומידך נתנו לך.
From You is everything, and from Your hand we give back to You.