Example, when Abraham and Sarai, was so eager to have their own offspring, took so long until Sarai was pregnant with Isaac at age 80 ! Impossible at today's feat. This is while Abraham see his neighbors can get pregnant at 30, if his faith wasn't strong, he would have grind his teeth and said why I get child at 80? But my friend here get child at 30?

God's work on Jacob shows the experience of God the Spirit-how God disciplined him, dealt with his natural life, and weakened him, how God caused Christ to be formed in him through the constitution of the Holy Spirit, and how he bore the fruit of the Holy Spirit.

Wow ... you just show something mysterious about the Trinity. The fact that Holy Spirit  = God, and God = Holy Spirit shows the high matter of coinherence.

The Father is in the Son and in the Spirit; the Son is in the Father and in the Spirit; and the Spirit is in the Father and in the Son. They are three, yet They are mingled together as one. This is coinherence. The Three of the Godhead not only coexist but also coinhere. Coinherence is a mutual indwelling or a mingling.

Your latter statement, "...means there are only 2 Gods in Christian i.e Jesus and God / Holy Spirit. Means, trinity concept is not trinity anymore." shows that you might not understand what the term "Trinity" means ...

Allah is a noun.

Nope I didn't say that.

When Christian uses Allah, it is a generic term for God. It is not WHICH GOD are we referring to.

BUT when we refers to God, it is the Triune God (singular) that we are referring to. According to the Bible, God is uniquely one (Deut. 6:4; 1 Cor. 8:6), yet He is also the Father, the Son, and the Spirit (Matt. 28:19b). This is difficult for the human mind to reconcile or explain, but this is the revelation in the Bible.

The Father, the Son, and the Spirit coexist with one another (Matt. 3:16-17; Eph. 3:14-17), and They also coinhere. To coexist means to exist together at the same time. To understand the coexistence of the three of the Divine Trinity is not difficult, but to understand how the three of the Divine Trinity coinhere is very difficult. To coinhere means that the three of the Divine Trinity exist within one another, abide in each other (John 14:10-11; 17:21). The three of the Divine Trinity from eternity past have been and still are coexisting and coinhering with one another.
The three of the Divine Trinity are distinctly three and yet one. The Father is distinct from the Son, the Son is distinct from the Spirit, and the Spirit is distinct from the Father and the Son.

Yet the Son is the Father (Isa. 9:6; John 14:9-10), and the Son is also the Spirit (2 Cor. 3:17). The Son became flesh (John 1:1, 14) and was called the last Adam. This last Adam through death and resurrection became a life-giving Spirit (1 Cor. 15:45b). The son given was called the Eternal Father, and after His death and resurrection He became the life-giving Spirit. Therefore, the Son is both the Father and the Spirit.

HAHA ...

You have to study first what the word Trinity means and its implication

It's a common noun.

Back in the days prior to Islam, before Mohammamed was even born, the Arabs already using the word allah to refer to a divine deity.