robbing God of Glory

does it rob God of Glory to have intercession of the saints or people participating with grace?

Because God is love he gave us real causal powers

Because God is love, He does not do everything Himself. He created us, and gave us real causal powers. So, He doesn’t operate by the principle, “If I can do it, then there is no point in having anyone else do it.” He works by love, which is the very opposite of such egoism, because by love He gives to us the dignity of participation in His glorious activity. This is what we mean in speaking of His love as self-effusive. Strictly speaking, God did not need to give us causal powers of any sort. God could have done everything, entirely, Himself. He loves to give to us the opportunity to participate as real [secondary] causes in His work. That’s one of the gifts He has given to the saints in heaven, by allowing them to be genuine intercessors on our behalf.

from comment 7 :

http://www.calledtocommunion.com/2009/08/a-catholic-reflection-on-the-meaning-of-suffering/

Is God's glory diminished if man participates in grace?

Michael’s concern is that the doctrine that man participates in his salvation takes some glory away from God, and gives it to man. This concern is based on three implicit philosophical assumptions:

(1) that God gets the most glory when God alone receives glory,

(2) that glory is the sort of thing that is lost by the giver when the giver gives it to others,

and

(3), that the degree of glory is determined entirely by the degree of causality exercised, such that the greater the causality exercised, the greater the glory.

But each of these three assumptions is not true. If (2) and (3) were true, then God would lose glory by creating creatures and giving them actual causal powers, since St. Paul tells us that creatures already have glory simply by the kind of nature that they have. (1 Cor 15:41) Moreover, if each of these three assumptions were true, then if God wished to maximize His glory, He would have either to avoid creating anything at all, or He would have to give only the illusion of causal powers to creatures, reserving all causality to Himself. This position is called occasionalism, and I have discussed it elsewhere.

Let’s consider what St. Thomas Aquinas says about this  [go here for his quotes from Aquinas on this: http://principiumunitatis.blogspot.com/2009/02/gospel-and-paradox-of-glory.html

see also:  http://principiumunitatis.blogspot.com/2008/06/monocausalism-salvation-and.html