Who Does God Swear By - Bible vs Koran

But the angel of the Lord called to him from heaven and said, "Abraham, Abraham!"
He replied, "Here I am."
Then he said, "Do not lay a hand on the boy or do anything to him. For now I know that you fear God, since you have not withheld your only son from me." Abraham looked up and saw a ram caught in the thicket by its horns. So Abraham went and took the ram and offered it as a burnt offering in place of his son. And Abraham named that place The Lord Will Provide, so today it is said, "It will be provided on the Lord's mountain."
Then the angel of the Lord called to Abraham a second time from heaven and said, "By myself I have sworn," this is the Lord's declaration: "Because you have done this thing and have not withheld your only son, I will indeed bless you and make your offspring as numerous as the stars of the sky and the sand on the seashore. Your offspring will possess the city gates of their enemies. And all the nations of the earth will be blessed by your offspring because you have obeyed my command." (Genesis 22:11-18 CSB)

After Abraham proved his faith in God by offering Isaac as a sacrifice, God replaced Isaac with a ram and swore to Abraham that He will multiply Abraham's descendants. This event is also celebrated by the Muslims in Eid al-Adha (Hari Raya Haji).

In the Bible, God can only swear by Himself because there is no one greater than Him.

For when God made a promise to Abraham, since he had no one greater to swear by, he swore by himself: I will indeed bless you, and I will greatly multiply you. And so, after waiting patiently, Abraham obtained the promise. For people swear by something greater than themselves, and for them a confirming oath ends every dispute. (Hebrews 6:13-16 CSB)

In the Quran, Allah swears by all kinds of stuff. Below is quoted from the WikiIslam article Swears and Oaths in the Qur'an and Hadith - WikiIslam:

QUOTE
The following are verses from the Qur'an, where we find Allah swearing oaths.
I swear by the Book that makes manifest (the truth). (Quran 44:2)
Qaf. I swear by the glorious Quran (that Muhammad is the Messenger of Allah) (Quran 50:1)
I swear by the wind that scatters far and wide, (Quran 51:1)
I swear by the Mountain, (Quran 52:1)
I swear by the star when it goes down. (Quran 53:1)
But nay! I swear by the falling of stars; (Quran 56:75)
Noon. I swear by the pen and what the angels write, (Quran 68:1)
Nay; I swear by the moon, (Quran 74:32)
Nay! I swear by the day of resurrection. (Quran 75:1)
I swear by the emissary winds, sent one after another (for men's benefit), (Quran 77:1)
I swear by the angels who violently pull out the souls of the wicked, (Quran 79:1)
I swear by the mansions of the stars, (Quran 85:1)
I swear by the heaven and the comer by night; (Quran 86:1)
I swear by the daybreak, (Quran 89:1)
Nay! I swear by this city. (Quran 90:1)
I swear by the sun and its brilliance, (Quran 91:1)
I swear by the night when it draws a veil, (Quran 92:1)
I swear by the early hours of the day, (Quran 93:1)
I swear by the fig and the olive, (Quran 95:1)
I swear by the runners breathing pantingly, (Quran 100:1)
I swear by the time, (Quran 103:1)
UNQUOTE