user10831: I am reading
 "A Critical Analysis Of The Jhanas"
And it's talking about the way to reach the first jhana. This passage below.

Block quote
  The Pa:isambhidāmagga explains them as follows: 
  For one developing the first jhāna, the hindrances are abandoned by way of 
  suppression. For one developing concentration partaking of penetration, 
  wrong views are abandoned by way of substitution of opposites. For one 
  developing the supramundane path that leads to their destruction, 
  (defilements) are abandoned by way of cutting off. At the moment of fruition 
  they are abandoned by way of tranquillization. And abandoning by deliverance 
  is nibbāna, cessation.2
   (Wr. tr.).
  `

The question is, isn't the first jhanas all about concentration? So why did it say if you want to reach the first jhana you must partake in abandonment by suppression, and to reach concentration you must abandoned by way of substitution of opposites. Isn't it all dedicated to concentration?

user10641: 
why did it say if you want to reach the first jhana you must partake
  in abandonment by suppression?

Because for the First Jhana to arise the Five hindrances must be abandoned.
You abandon it by focusing on one object.
By doing so you blot out the hindrances.
The more you focus on one object the more  the hindrances gets blotted out and suppressed.

(So why did it say) to reach concentration you must abandoned by way of substitution of
  opposites.

For example if a smoker wants to abandon smoking he substitues it with nicotin patches.
If you want to abandon the hindrances you substitute it with the Opposites.(Jhana Factors).
So how do you substitute it with the Jhana factors.You don't have to go looking for the Jhana factors.Just by doing one simple action of focusing on one object. The mind gathers/collects itself.And the Jhana factors (The opposites) arise naturally.On its own.
Each Jhana factor is the opposite of each hindrance.
There are five hindrances and they each have an opposite (Jhana Factor).
1.Sensual pleasures X One pointedness.
2.Ill Will X Rapture.
3.Restlesness X Happiness
4.Sloth and torpor X Vitakka. 
5.Doubt X Vicara. 

The question is, isn't the first jhanas all about concentration? Isn't
  it all dedicated to concentration?

Yes Jhana is about developing concentration.But you have to ask yourself What is Concentration? Concentration has many levels,but generally it's the state of mind that isn't obstructed by the hindrances.By practicing the Jhanas you are systematically letting go/abandoning the hindrances by means of suppression and subtituting it with the opposites.We need concentration to see clearly.When you see thing clearly you realise the truth and attain liberation.

user-1: I think this passage is addressing something that's more explicitly stated elsewhere.  In the Jhana Sutta (AN 9.36), for example, we find:  

secluded from sensuality, secluded from unskillful qualities, [he] enters &
  remains in the first jhana: rapture & pleasure born of seclusion,
  accompanied by directed thought & evaluation.

The operative word here, of course, is "secluded".  Vitaka and vicara (i.e. concentration) only come into the equation once rapture and pleasure are born of that seclusion.  Piti and sukkha help to calm, gladden, and focus the mind allowing concentration to strengthen in to full jhana.  
So of course, this begs the question of how one finds that seclusion.  There are some who are lucky and can just shut the door on their negative and unwholesome states.  Other have to win their seclusion through other methods like suppression and substitution of opposites.  I think the latter group is who your quoted passage is addressing.   

10831: <p>I am reading
 "A Critical Analysis Of The Jhanas"</p>

<p>And it's talking about the way to reach the first jhana. This passage below.</p>

<blockquote>
  <p>Block quote
  The Pa:isambhidāmagga explains them as follows: 
  For one developing the first jhāna, the hindrances are abandoned by way of 
  suppression. For one developing concentration partaking of penetration, 
  wrong views are abandoned by way of substitution of opposites. For one 
  developing the supramundane path that leads to their destruction, 
  (defilements) are abandoned by way of cutting off. At the moment of fruition 
  they are abandoned by way of tranquillization. And abandoning by deliverance 
  is nibbāna, cessation.2
   (Wr. tr.).
  `</p>
</blockquote>

<p>The question is, isn't the first jhanas all about concentration? So why did it say if you want to reach the first jhana you must partake in abandonment by suppression, and to reach concentration you must abandoned by way of substitution of opposites. Isn't it all dedicated to concentration?</p>
 10641: <blockquote>
  <p>why did it say if you want to reach the first jhana you must partake
  in abandonment by suppression?</p>
</blockquote>

<p>Because for the First Jhana to arise the Five hindrances must be abandoned.</p>

<p>You abandon it by <strong>focusing on one object.</strong></p>

<p>By doing so you <strong>blot out</strong> the hindrances.</p>

<p>The more you focus on <strong>one object</strong> the more  the hindrances gets <strong>blotted out</strong> and <strong>suppressed.</strong></p>

<blockquote>
  <p>(So why did it say) to reach concentration you must abandoned by way of substitution of
  opposites.</p>
</blockquote>

<p>For example if a smoker wants to abandon smoking he substitues it with nicotin patches.</p>

<p>If you want to abandon the hindrances you substitute it with the Opposites.(Jhana Factors).</p>

<p>So how do you substitute it with the Jhana factors.You don't have to go looking for the Jhana factors.Just by doing one simple action of <strong>focusing on one object.</strong> The mind gathers/collects itself.And the Jhana factors (The opposites) arise naturally.On its own.</p>

<p>Each Jhana factor is the opposite of each hindrance.</p>

<p><strong>There are five hindrances and they each have an opposite (Jhana Factor).</strong></p>

<p><strong>1.Sensual pleasures X One pointedness.</strong></p>

<p><strong>2.Ill Will X Rapture.</strong></p>

<p><strong>3.Restlesness X Happiness</strong></p>

<p><strong>4.Sloth and torpor X Vitakka.</strong> </p>

<p><strong>5.Doubt X Vicara.</strong> </p>

<blockquote>
  <p>The question is, isn't the first jhanas all about concentration? Isn't
  it all dedicated to concentration?</p>
</blockquote>

<p>Yes Jhana is about developing concentration.But you have to ask yourself <strong>What is Concentration?</strong> Concentration has many levels,but generally it's the state of mind that isn't obstructed by the hindrances.By practicing the Jhanas you are systematically letting go/abandoning the hindrances by means of suppression and subtituting it with the opposites.We need concentration to see clearly.When you see thing clearly you realise the truth and attain liberation.</p>
 -1: <p>I think this passage is addressing something that's more explicitly stated elsewhere.  In the Jhana Sutta (AN 9.36), for example, we find:  </p>

<blockquote>
  <p>secluded from sensuality, secluded from unskillful qualities, [he] enters &amp;
  remains in the first jhana: rapture &amp; pleasure born of seclusion,
  accompanied by directed thought &amp; evaluation.</p>
</blockquote>

<p>The operative word here, of course, is "secluded".  Vitaka and vicara (i.e. concentration) only come into the equation once rapture and pleasure are born of that seclusion.  Piti and sukkha help to calm, gladden, and focus the mind allowing concentration to strengthen in to full jhana.  </p>

<p>So of course, this begs the question of how one finds that seclusion.  There are some who are lucky and can just shut the door on their negative and unwholesome states.  Other have to win their seclusion through other methods like suppression and substitution of opposites.  I think the latter group is who your quoted passage is addressing.   </p>
