I am working on a gnome character that I started as a cleric and gave rogue level to afterwards. He is now Cleric 3/Rogue 4. I am worried that if I go too far in one class, the other will not be very useful. If I go more cleric levels, his rogues abilities suffer. If I go more rogue, His healing abilities will not be very good. Any ideas?
You should have gone with more cleric levels that rogue, since you're now a 7th level character casting 2nd level spells instead of 4th level spells. Try to stick with spells that have a set effect, instead of those very dependant upon caster level and saving throws. Multiclassing like this hurts your cleric abilities far more than it does your rogue abilities.
Ask yourself what the rogue gives you that you absolutely need. If you're only taking rogue for flavor reasons, then you can probably just flavor your character that way. If you just want a lot of skills, you might find another way to get skills or have a higher than normal Intelligence. If you want Sneak Attack (which is pretty meh when you multiclass anyways), you might just find other ways to get bonus damage and reflavor them.
If you want a sort of tricky cleric, Travel and Luck are pretty strong, and may be one of the stronger domain combinations that clerics can get. There are ways to act sort of rogue-like without actually being a rogue, including Bard archetypes; in fact, if you wanted, you could potentially pull off a cleric/rogue with the correct Bard build.
That kind of base almost begs for some kind of prestige class or additional multi-classing. What exactly does this character do in combat? Out of combat?
Perhaps either taking 2 more levels of cleric or if possible retraining 2 levels of rogue to cleric (that could get pricey) and then going Loremaster? The class would advance your casting while giving out a fair amount of skill points and giving nice peripheral benefits.
Too bad there isn't a prestige class that improves BOTH channel energy and sneak attack using the same pool of power. They're both d6s that increase at every other level, so they do have some mechanical relatedness.
I am working on a gnome character that I started as a cleric and gave rogue level to afterwards. He is now Cleric 3/Rogue 4. I am worried that if I go too far in one class, the other will not be very useful. If I go more cleric levels, his rogues abilities suffer. If I go more rogue, His healing abilities will not be very good. Any ideas?
IMO, you already went too far with rogue levels. For a 9-level caster, you should try to give up no more than 2-3 levels of spell progression in most cases (to maintain access to 9th-level spells); especially with a cleric, druid, or oracle, since they are already pretty combat-effective (arcanists, sorcerers, witches, and wizards may need to give up a bit more to be an effective combatant, depending on the details). Uncanny Dodge is nice, but not as good as many spells; the Extra Rogue Talent feat can be used to gain additional talents without taking more levels in rogue.
You may want to talk to your GM about Retraining your 4th rogue level into a 4th cleric level (and possibly your 7th character level feat into Extra Rogue Talent, depending on whether the currently selected talent or feat is more important to the concept). Straight cleric on out (or a prestige class with full casting) will still net a strong caster with +2d6 Sneak Attack. As a cleric, you have plenty of buff spells to improve your combat capabilities; Sneak Attack is a nice bonus, but more tricky to pull off consistently. About the only drawback to a cleric is the lack of Skill Ranks; still, as long as you have a 12 Int, maxing Disable Device and Perception is doable (splitting the remaining ranks in Knowledge (Religion) and probably one or more of Diplomacy, Knowledge (Local), and Spellcraft; if you selected cleric as your favored class, then the using the bonus for +1 skill rank each cleric level can help with developing more skills).
You're all assuming this guy wants full cleric casting. To OP, of you do want to have a "relevant" caster then the advice given is spot on.
If yoi want a rogue with a dash of something else for utility, just have a look what exactly you want from cleric, particularly what spells. This will let you know how many caster levels you need.
Regardless which you pick, have a look at Magical Knack trait which lets you count as 2 levels higher (up to HD) in a spellcasting class you posses for the effects of its spells (i.e. cure moerate with c3/r4 heals 2d8+5, instead of 1d8+3, divine favour counts as a cleric of 5th level, etc).
Weird Intelligence/dex focused Rogue/Cleric:
8 levels Divine Strategist (int to hit when flanking, lvl 8)
3+ Rogue
Domain: Crocodile (1d6 sneak at 6th)
Perhaps pick up Spring Attack when taking rogue levels
How to play?
First levels you play straight up cleric (perhaps 1 level in rpgue early for skills and sneak) and buff/support, focus on skills too. You're a good support and durable if you want (spells).
Later, after cleric 8 and more so rogue 3, flank, hit and never miss. Play more like a rogue.
Consider: Outflank for all your team and keen kukris with Butterfly Sting, and a flanking buddy with a high crit weapon. Praise Desna!
This gets you (at 11):
Int to hit, Dex to hit and Damage
Initiative boost +4
High Int high Dex, wisdom only needs a 14 at 11th, easy
Some sneak attack (3d6), with high chance to hit
4th level cleric spells, some great buffs here, much problem solving too
Weirder still:
VMC into Wizard Foresight (rerolls int times per day)
Or
VMC magus for the arcanas, letting you target flat footed or add int tp hit.
I prefer to play the above build with the Animal, Feather domains, giving you a flanking buddy if your team isnt the right composition.
Remember just cause you play with some cleric levels doesnt mean you are a heal bot. You can flavour things as you like. Youre there m ostly to flank and provide support, and otherwise have skills (hey, same as a rogue).
Check out the gnome racial feats, esp Gnome Trickster. This grants you mage hand. Speak With Animals is a 3rd level arcane (bard) spell and so you then qualify for arcane trickster. (Which would then advance your cleric casting..)
As for channelling look into variant channeling rules.
Which traits/archetypes/feats/domains did you choose?
Yeah well: ask the DM to houserule it? There's a dearth of divine trickster options available though it is a common gnomish trope.
really, other than a couple of Rouge Talents a Sanctified Slayer Inquisitor fits the mold of Cleric/Rogue.
If you want Rogue Talents take two levels of Rogue, go the rest SS Inquisitor and take the Extra Rogue Talent Feat as needed.