The meaning of this hadith is that when you do any type of work, then think before carrying ot out. Delibarate upon it from all angles then go on to it. As if the affair does not work out then the first thought that comes into the head is that it was from shaytaan, so firstly look at a prospective affair from all angels then carry it out or not.
But in regards to affairs concenrning Allah and His deen then you should hurry in to them, as Allah has mentioned one of the qualities of the pious as those who hurry towards good.
وَ يُسَارِعُوْنَ فِي الْخَيْرَات
Mulla Ali Qari (RahmiuAllah alayh) mentions:
When starting any form of worship or work for deen, one should hurry in starting it. When in the midst of the worship not to hurry is what is mentioned in this hadith, as rushing through ibadah is from shaytaan, for example rushing towards praying salah, one should hurry towards starting the worship but not during the salah.
In terms of affairs of this world, all a Muslim could ask for is that the affairs for this world are good for him in this world and the hereafter. For this our beloved Prophet Muhammad (Peace and blessings of Allah be upon him) has taught us the prayer of istikhara.
When someone is in a dilemma, or has to make a very important decision, one ought to pray two rak’ahs of nafl salah, and ask Allaah Subhaanahu wa Ta’aala for guidance by supplicating in the following manner.
Arabic (click image for larger version):
Allāhumma innē astakhēruka bi’ilmika wa astaqdiruka bi qudratika wa as`aluka min fadlikal ‘azēm. Fa`innaka taqdiru wa lā aqdiru wa ta’lamu wa lā a’lamu wa anta ‘allāmul ghuyūb. Allāhumma in kunta ta’lamu anna hādhal amra khairullē fē dēnē wa ma’āshē wa ‘āqibati amrē ao’ājili amrē wa`ājilihē faqdirhu lē wa yassirhu lē thumma bārik lē fēhi. Wa in kunta ta’lamu anna hādhal amra sharrullē fē dēnē wa ma’āshē wa’āqibati amrē ao’ājili amrē wa`ājilihē fasrifhu ‘annē wasrifnē ‘anhu waqdirlil khaira haithu kāna thummardinē bihē.
O Allaah, I ask You to show me what is best, through Your knowledge, and I ask You to empower me, through Your Power, and I beg You to grant me Your tremendous Favor, for You have Power, while I am without power, and You have Knowledge, while I am without knowledge, and You are the One who Knows the unseen. O Allaah, if you Know that this is good for my worldly life and for the Hereafter, then destine it for me and make it easy for me, and put Blessing in it. And if you Know it to be of bad consequences for me in my worldly life and for the Hereafter, then distance it from me, and distance me from it. And give me the ability to do that which is beneficial for me, and keep me pleased with that.
In place of "haadhal amra" (this/it), one should mention one’s necessity/decision.
Source: Al-Hisnul Haseen.Duas Requested
وَ عَلَيْكُمْ السَّلامْ وَ رَحْمَةُ اللهِ وَ بَرَكات