Question

Can a spell with both somatic components and material, focus, or divine focus components be cast with only one free hand?

To clarify further…

1. What does it mean to prepare material components?
2. What does it mean to manipulate material, focus, or divine focus components?
3. Must a caster have at least one free hand to prepare and manipulate material components for a spell requiring material components? Must a caster have at least one free hand to manipulate the focus or divine focus component for a spell requiring a focus or divine focus component?
4. Must a caster have at least two free hands to cast a spell having both somatic and material components, one hand for gestures and a second, different hand for preparing and manipulating the material components? Must a caster have at least two free hands to cast a spell having both somatic and focus or divine focus components, one hand for gestures and a second, different hand for manipulating the focus or the divine focus components?
5. Must a divine focus routinely be manipulated to cast a spell?

I am well aware of and uninterested in the feats Eschew Materials (PH 94) and Still Spell (PH 101) and other character, spell, and equipment options. This isn't a how-can-I-do-it question; it's a how-does-it-work question.

Sometimes I overthink things and miss the obvious; this might be the case. Seriously, if the answer's like on page 4 of the Player's Handbook or something, that's cool, but I did do some research; see below for results.

Background

@KRyan's comment on my answer to this question reminded me of this nagging question. In my experience a caster keeps one hand (relatively) free to cast spells, but I've never seen addressed that many spells require preparing and manipulating material components, and that this inconvenience might occupy both the typical caster's hands were the spell also to possess somatic components. Although maybe it's my limited imagination, I usually read preparing and manipulating as being done with an otherwise empty hand.

But I've never had a DM mandate a caster needs at least two hands free to cast a spell with both somatic and material components nor have I mandated such as a DM. I don't know why. Now I'm wondering if I should've been playing and DMing this way all along.

From the Player's Handbook

The section Cast a Spell under the heading Spell Components reads, in part,

To cast a spell with a somatic (S) component, you must gesture freely with at least one hand. You can’t cast a spell of this type while bound, grappling, or with both your hands full or occupied (swimming, clinging to a cliff, or the like).

To cast a spell with a material (M), focus (F), or divine focus (DF) component, you have to have the proper materials, as described by the spell. Unless these materials are elaborate […] preparing these materials is a free action. (140)

Emphasis mine. To avoid absurdity, let's assume that have means currently possess in an easily accessible place on the caster's person. I honestly don't know what to do about prepare, though. For what it's worth, I think the only other mention of preparing spell components is on page 141's Table 8-2: Actions in Combat under the heading Free Action with the entry Prepare spell component to cast a spell listed as not provoking attacks of opportunity.

The section If You're Grappling under the heading Cast a Spell reads, in part,

You can attempt to cast a spell while grappling or even while pinned […], provided [the spell's] casting time is no more than 1 standard action, it has no somatic component, and you have in hand any material components or focuses you might need. (156)

Emphasis mine. While grappling, at least, it's clear the material, focus, and maybe divine focus (see below) components are held in a hand, but hands can't be used for casting a spell because of the grapple, therefore the question remains unresolved.

The section Choosing a Spell reads, in part,

To cast a spell, you must be able to speak (if the spell has a verbal component), gesture (if it has a somatic component), and manipulate the material components or focus (if any). (170)

Emphasis mine. No mention's made–obviously–of what this manipulation requires. It's a mystery.

From Dungeonscape

In the section Weapon and Armor Modification is the armor and shield modification sanctified which reads, in part,

This modification makes the armor a legitimate divine focus for divine spellcasters of that faith. Normally, a divine focus does not have to be in hand to cast a spell, so a sanctified shield is a matter of personal style for clerics who prefer a shield to an amulet. (34)

Emphasis mine. And by a strict–some would say tortured–reading this is correct. The If You're Grappling and Choosing a Spell rules I quoted above don't call out divine focuses, which are technically different from just focuses, so a divine focus needn't be in hand or manipulated to cast a spell. But, wow, Dungeonscape, that seems very counter to the intent.

"Who Cares?"

If manipulating material components requires at least one free hand, it's another strike against gishes. The 3rd-level Sor/Wiz spell displacement [illus] (PH 223) has only vocal and material components, so a dual-wielding gish who must use a free hand to manipulate the material components struggles to cast it as well as spells like the 2nd-level Sor/Wiz spell darkness [evoc] (PH 216) and the 3rd-level Sor/Wiz spell suggestion [ench] (PH 285). And, obviously, all the spells with both somatic and material, focus, or divine focus components. Further, if casters need at least two free hands free to cast spells with somatic and material, focus, or divine focus components clerics become less formidable.

Other Sources

I searched the Rules Compendium for information about this topic, but it was no help. Dungeonscape's sanctified armor was an oddity that I remembered from a while back. However, I've not searched other sources for more information about preparing material components and manipulating material, focus, and divine focus components.