“…to which He called you by our gospel, for the obtaining of the glory of our Lord Jesus Christ“
The “which” here refers to the word “salvation” of the previous verse.
He called you
Verse 13 says that God “chose” us. This verse says that He “called” us (Romans 8:28-30; 1 Corinthians 1:9, 23,24; Galatians 1:15,16; Philippians 3:13,14; Hebrews 13:1; 1 Peter 2:9; 5:10). God “called” us (past tense).
The gospel flies in the face of the prevailing philosophy of the world. It does not make any sense to those without Christ. They cannot understand why people need salvation.
“…but we preach Christ crucified, to the Jews a stumbling block and to the Greeks (Gentiles) foolishness…” (1 Corinthians 1:23).
God has a purpose and program for each child of His. He providentially organized His program from eternity. He has not overlooked any detail of your life. He arranged everything that happens to you and every person you meet.
“…who has saved us and called us with a holy calling, not according to our works, but according to His own purpose and grace which was given to us in Christ Jesus before time began…” (2 Timothy 1:9).
Christians hold the high privilege of representing King Jesus on earth, so they should carry the dignity of being children of God.
The Christian has a high and heavenly calling. It is a high privilege to represent the King, to be a child of the King. That is why we do not think or act like those who do not know Christ. We hold a high privilege. We carry dignity by our association with King Jesus.
Some things are beneath the dignity of the child of the King. We choose not to indulge in certain things, not because they are wrong, but because they are simply beneath the dignity of someone representing the Lord of lords.