न च विद्यासमो बन्धुः

न च विद्यासमो बन्धुर्न च व्याधिसमौ रिपुः।
न चापत्यसमः स्नेहो न च दैवात्परं बलम्‌॥
na ca vidyāsamo bandhurna ca vyādhisamau ripuḥ |
na cāpatyasamaḥ sneho na ca daivātparaṁ balam ||
There is no relative (well-wisher) equal to knowledge, no enemy as bad as disease;
No affection is equal to that for a child and  there is no power greater than that of God (destiny?).

ललाटलेखा न पुनः प्रयाति

लब्धव्यमर्थं लभते मनुष्यो देवोऽपि तं वारयितुं न शक्तः।
अतो न शोचामि न विस्मयो मे ललाटलेखा न पुनः प्रयाति॥
labdhavyamarthaṁ labhate manuṣyo devo’pi taṁ vārayituṁ na śaktaḥ |
ato na śocāmi na vismayo me lalāṭalekhā na punaḥ prayāti ||
Man obtains wealth he is to obtain, even God (Deva) is not able to prevent it.
Therefore, I neither grieve nor get surprised as the writing on the forehead never fails.

[Thanks to sanskritdocuments.org]

दैवं फलति सर्वत्र

दैवं फलति सर्वत्र न विद्या न च पौरुषम्।
समुद्रमथनाल्लेभे हरिर्लक्ष्मीं हरो विषम्॥

(It is) destiny that reaps (results) everywhere, not learning and not effort.
From the churning of the ocean, Hari obtained Lakshmi, Shankar, poison.

(Kindly contributed by Ms. Uma Purang)

नश्यति प्रज्ञा

अथवा नश्यति प्रज्ञा प्राज्ञस्यापि नरस्य हि।
प्रतिकूले गते दैवे विनाशे समुपस्थिते॥
athavā naśyati prajñā prājñasyāpi narasya hi|
pratikūle gate daive vināśe samupasthite||
The intelligence of even a wise man perishes,
when fate is unfavourable and destruction is imminent.

विनाशकाले विपरीतबुद्धिः
vināśakāle viparītabuddhiḥ

देवः तत्र सहायकृत्‌

उद्यमस्साहसं धैर्यं बुद्धिश्शक्तिः पराक्रमः।
षड् एते यत्र वर्तन्ते देवः तत्र सहायकृत्‌॥
udyamassāhasaṁ dhairyaṁ buddhiśśaktiḥ parākramaḥ |
ṣaḍ ete yatra vartante devaḥ tatra sahāyakṛt ||

"Industriousness, adventure, courage, intelligence, strength and adventuorous accomplishment; where these six qualities exist, God provides assistance."
[Thanks to Kedar]

अरक्षितं तिष्ठति दैवरक्षितं

अरक्षितं तिष्ठति दैवरक्षितं
सुरक्षितं दैवहतं विनश्यति।
जीवत्यनाथोऽपि वने विसर्जितः
कृतप्रयत्नोऽपि गृहे विनश्यति॥
— पञ्चतन्त्रम् – मित्रभेदः – कथामुखम् २०
arakṣitaṁ tiṣṭhati daivarakṣitaṁ
surakṣitaṁ daivahataṁ vinaśyati|
jīvatyanātho'pi vane visarjitaḥ
kṛtaprayatno'pi gṛhe vinaśyati||
— pañcatantram – mitrabhedaḥ – kathāmukham 20

"The helpless can survive if protected by destiny, while the secure may perish when ill-fated. The orphaned child abandoned in the forest can survive whereas, by contrast, another may perish at home in spite of all precautions and efforts."

विनाशकाले विपरीतबुद्धिः

न भूतपूर्वं न कदापि वार्ता हेम्नः कुरङ्गो न कदापि दृष्टः।
तथापि तृष्णा रघुनन्दनस्य विनाशकाले विपरीतबुद्धिः॥
na bhūtapūrvaṁ na kadāpi vārtā hemnaḥ kuraṅgo na kadāpi dṛṣṭaḥ|
tathāpi tṛṣṇā raghunandanasya vināśakāle viparītabuddhiḥ||

"It had neither happened before nor heard; nor had a golden deer ever been seen;
Even then, Rama desired it — one's thinking goes amiss in bad times!"

विनाशकाले विपरीतबुद्धिः is such a famous quote, but would one think it would be from Ramayana, and that too describing Rama! One would have expected it to be describing one of the bad characters such as दुर्योधनः or रावणः! That's what destiny is… it impels even the great to err…

उद्यमेन हि सिध्यन्ति

उद्यमेन हि सिध्यन्ति कार्याणि न मनोरथैः।
न हि सुप्तस्य सिंहस्य प्रविशन्ति मुखे मृगाः॥
udyamena hi sidhyanti kāryāṇi na manorathaiḥ|
na hi suptasya siṁhasya praviśanti mukhe mṛgāḥ||

"Endevaours succeed only by effort, not by mere thoughts (wishes);
Animals do not enter the mouth of a sleeping lion." Further,

उद्योगिनम् पुरुषसिंहमुपैति लक्ष्मीः
दैवेन देयमिति कापुरुषा वदन्ति।
दैवं निहत्य कुरु पौरुषम् आत्मशक्त्या
यत्ने कृते यदि न सिध्यति कोऽत्र दोषः॥
udyoginam puruṣasiṁhamupaiti lakṣmīḥ
daivena deyamiti kāpuruṣā vadanti|
daivaṁ nihatya kuru pauruṣam ātmaśaktyā
yatne kṛte yadi na sidhyati ko'tra doṣaḥ||

Lakshmi goes to the industrious lion-like man;
Only contemptible cowards say that destiny should give;
Overcome your destiny and exercise your internal strength;
If there is no accomplishment inspite of effort where is the fault (who is to blame)?

To end with a note from the Bhagavad-gita:
काङ्क्षन्तः कर्मणां सिद्धिं यजन्त इह देवताः।
क्षिप्रम् हि मानुषे लोके सिद्धिर्भवति कर्मजा॥
—भगवद्गीता ४-१२
kāṅkṣantaḥ karmaṇāṁ siddhiṁ yajanta iha devatāḥ|
kṣipram hi mānuṣe loke siddhirbhavati karmajā||
—bhagavadgītā 4-12

Men seeking fruition of activities worship the gods;
In this world of of human beings, success born of actions follows quickly.
It is worth noting that सिद्धिर्भवति कर्मजा is the slogan of IIT Madras.