Hebrews 12:8 But if you be without chastisement, whereof all are partakers, then are you bastards, and not sons. 

‘Without chastisement’ – If you are not chastened you are not a child of God, but a child of satan – he whom you obey and follow you are a child of and he is your father (John 8:44). Either our consequences will pull us towards God to life in obedience to His Word so that we can be under His protection (Ps. 91), or we will rebel, complain and blame and move away even further from Him and play right into the enemy’s hand who will bring destruction to our lives (John 10:10; 1Pet. 5:7-8).

Ephesians 1:5 says we are predestined unto adoption to become children [of God] by Jesus Christ to himself. Predestinated [Greek: proorizo] means foreordained. Here God has predestined all children of God to be adopted into His family, but who becomes a child of God is left up to each individual (John 3:15-20; Rev. 22:17; cp. 1Tim. 2:4; 2Pet. 3:9).

The child of God must be led by the Spirit, to live and walk in the Spirit, and to meditate on His Word and to obey it – if he is to have success and live a Christian life (Rom. 8:1-16; Gal. 5:16-26; Jos. 1:8; Ps. 1:3-4).

‘All are partakers’ – referring to all true Christians who follow Christ according to Biblical standards (1Pet. 2:21-23) and don’t live in sin any longer (Rom. 6; 1Jn. 3).