15 And the angel of the LORD called to Abraham a second time from heaven
16 and said, “By myself I have sworn, declares the LORD, because you have done this and have not withheld your son, your only son,
17 I will surely bless you, and I will surely multiply your offspring as the stars of heaven and as the sand that is on the seashore. And your offspring shall possess the gate of his enemies,
18 and in your offspring shall all the nations of the earth be blessed, because you have obeyed my voice.”
In Genesis 3:15, God said that Eve’s offspring would crush the head of the serpent. Look now at Genesis 22:18. This is story of Abraham and Isaac. Father Abraham took his one and only son up the mountain to die. Abraham trusted in the Lord. But the Lord did not provide an alternative. So Abraham built an altar and trusted the Lord. But the Lord did not provide an alternative. So Abraham placed Isaac on the altar to kill him. The Lord stopped Abraham and provided him instead with a lamb. The Lord did provide that alternative and he did it whem Abraham showed he really did not doubt.
Abraham did not withhold his only son. But God also did not withhold his only son. In Genesis 22:18, the word offspring appears again. Like with Eve, it is a singular tense. God is not talking about all those who descended from Abraham. He is talking about one descendant through whom “all the nations of the earth” shall “be blessed.”
God keeps his promises. Here is the foreshadowing of Christ with Abraham. Thousands of years later that one offspring did bless all the nations.
But go back one more time to the scripture up top. Look what Abraham. He did not withhold his one and only son from the Lord and he trusted in the Lord. What are you withholding from the Lord? Anything? Give all to the Lord and trust him. Surrender your worries, your doubts, your treasure, and even your joy up to the Lord and watch him make you more joyous and more blessed daily.